Interactive visual analysis of contrast-enhanced ultrasound data based on small neighborhood statistics

To prospectively assess the diagnostic performance of contrast-enhanced ultrasound (CEUS) and MR imaging in incidental solid focal liver lesions not characterised on ultrasound. Forty-seven patients with 50 lesions underwent MR imaging and CEUS: 24 focal nodular hyperplasias (FNH), 11 adenomas, 10 haemangiomas, 1 focal fatty change and 4 malignant lesions were identified. Two experienced radiologists randomly reviewed contrast-enhanced MR imaging and CEUS data, and provided the most likely diagnosis. Sensitivity (Se), specificity (Sp), likelihood ratios (LR) and kappa value were calculated. A histotype diagnosis was obtained in 66-52% with MR imaging and 52-53% with CEUS, respectively, for both readers. Se, Sp and LR for haemangioma were 100-100, 100-100 and 78-78 with MR imaging and 89-89, 100-100 and 68-70 with CEUS; for FNH with MR imaging they were 88-63, 96-100 and 23-34 and 74-67, 88-96 and 6-17 with CEUS. If the diagnosis of haemangioma was uncertain with CEUS, MR imaging always confirmed the diagnosis. If the diagnosis of FNH was uncertain with either CEUS or MR imaging, the other imaging technique confirmed the diagnosis in approximately half the cases. Both CEUS and MR imaging have a high diagnostic performance in incidental focal liver lesions and are complementary when diagnosis is uncertain.

The tracking-based semi-automatic software is a user-friendly tool to draw bounding box around focal liver lesions (FLLs) in Contrast-enhanced Ultrasound (CEUS) cine-loop based on MATLAB 2019b. The software development based on the consideration that deep learning has a broad prospect in processing FLLs CEUS cine-loops while extracting enormous ground-truth for detecting, tracking as well as further data analysis is necessary. Until now, there is no public software committing to successive extracting region of interests (ROIs) in CEUS cine-loops. The tracking algorithm build on point-based registration techniques (PBRTs) which are widely used for motion compensation in 2-D FLL CEUS imaging. The software need user draw a bounding box firstly for every tracking sequence and allows user to fine-tune or delete some bad tracking results in time. The software can show the dual bounding box when the cine-loop is in double display mode, all the functions for examples bounding box drawing and tracking can work directly in ultrasound in case that CEUS is unrecognizable. We also add some interactive items and sequence analysis algorithms to make the processing more efficient and you can download the software in https://github.com/Yuqi-Zest/CEUS-tracking-software.

To present a large monocentric experience in the characterization of focal liver lesions (FLLs) using Contrast Enhanced Ultrasound (CEUS). A retrospective study was performed in the Gastroenterology and Hepatology Department, Timisoara, including 1100 patients with 1329 FLLs evaluated between September 2009 and January 2013. A CEUS examination was considered conclusive if the FLL respected the typical enhancement pattern as described in the EFSUMB Guidelines. From the 1329 FLLs, CEUS was conclusive for a specific pathology in 1102 cases (82.9%). For the differentiation of benign/malignant lesions, CEUS reached a conclusive diagnosis in 1196 (90%) cases. The percentage of conclusive CEUS examinations was significantly higher in patients without chronic liver disease as compared with those with chronic hepatopathies: 87.3% vs. 74.4% (p<0.0001). CEUS patterns of enhancement fell into clear cut specific diagnostic patterns in 83% of the FLLs discovered by US, and into clear cut benign versus malignant patterns in 90% of the cases. For this reason, we can strongly recommend CEUS as a first line imaging method to characterize FLLs found at US, at least in centers with a good experience in CEUS.

Assessment of intraoperative quantitative shear wave elastography (SWE) and contrast-enhanced ultrasound (CEUS) for the characterization of focal liver lesions (FLLs) during liver surgery using postoperative histopathological results as the gold standard. US data of 79 consecutive patients with 98 FLLs who underwent liver surgery between 08/2015 - 06/2017 were prospectively acquired and retrospectively analyzed. Multifrequency linear/T-shaped probes (6 - 9 MHz) were used to store cine loops of at least 5 s and images of B-mode, SWE and CEUS. The first CEUS loop was continuously documented over 1 min. in each case. Quantitative SWE analysis of FLLs was performed by placing 5 regions of interest to measure shear wave speed (m/s) and stiffness (kPa). CEUS was evaluated during the arterial, portal venous and late phase after i. v. bolus injections of 2.4 - 10 ml sulfur hexafluoride microbubbles. Postoperative histopathology after tumor resection or intraoperative biopsy was obtained to confirm findings of SWE and CEUS. Of 98 FLLs in 79 patients (mean age: 58 years sd ± 12y) 88 were malignant and 10 were benign ranging from 0.69 to 15.2 cm in size (mean: 2.8 cm, sd ± 2.25 cm). SWE characterized 73/88 FLLs correctly as malignant and 7/10 as benign using a cut-off value of 2.5 m/s/21.3 kPa (p < 0.0005). The sensitivity was 83 %, specificity 70 %, accuracy 82 %. CEUS could correctly identify 86/88 malignant and 8/10 benign FLLs. The sensitivity was 98 %, specificity 80 %, accuracy 96 %. SWE could correctly identify 2 malignant FLLs which CEUS falsely characterized as benign. Intraoperative CEUS and SWE are excellent tools for the highly accurate visualization, characterization and malignancy assessment of hepatic tumors during liver surgery.

This review article provides an overview of the use of contrast-enhanced ultrasound (CEUS) in China. Currently, the only licensed contrast agent is SonoVue, a sulfur hexafluoride-filled microbubble contrast agent. In combination with a low mechanical index contrast-specific imaging mode, SonoVue-enhanced CEUS can be used to visualize the micro and macro-vasculature continuously. Since 2004, CEUS has been widely used in China in various clinical scenarios. The authors compared CEUS with baseline ultrasound or contrast-enhanced computed tomography with regard to characterization of focal liver lesions (FLLs). On CEUS, heterogeneous or homogeneous hyperenhancement during the arterial phase and washout in the portal/late phase are typical findings for hepatocellular carcinoma. The enhancement features of intrahepatic cholangiocarcinoma, infected FLLs, focal fatty infiltration, focal fatty sparing, complex cystic FLLs, and uncommon benign FLLs were carefully depicted. CEUS was also used for patient selection in ablation therapy and evaluation of response to ablation for liver cancer. The utility of three-dimensional CEUS of the liver was also explored. In non-liver use, CEUS in hilar cholangiocarcinoma, gallbladder, breast, and prostate was initially investigated. In addition, CEUS was used in interventional procedures such as CEUS-guided hemostatic injection, intraoperative CEUS in neurosurgery, and evaluation of response to high-intensity focused ultrasound ablation of uterine fibroids. The Chinese experience has resulted in increased use of CEUS.

The widespread use of computational simulation in science and engineering provides challenging research opportunities. Multiple independent variables are considered and large and complex data are computed, especially in the case of multi-run simulation. Classical visualization techniques deal well with 2D or 3D data and also with time-dependent data. Additional independent dimensions, however, provide interesting new challenges. We present an advanced visual analysis approach that enables a thorough investigation of families of data surfaces, i.e., datasets, with respect to pairs of independent dimensions. While it is almost trivial to visualize one such data surface, the visual exploration and analysis of many such data surfaces is a grand challenge, stressing the users' perception and cognition. We propose an approach that integrates projections and aggregations of the data surfaces at different levels (one scalar aggregate per surface, a 1D profile per surface, or the surface as such). We demonstrate the necessity for a flexible visual analysis system that integrates many different (linked) views for making sense of this highly complex data. To demonstrate its usefulness, we exemplify our approach in the context of a meteorological multi-run simulation data case and in the context of the engineering domain, where our collaborators are working with the simulation of elastohydrodynamic (EHD) lubrication bearing in the automotive industry.

To assess the value of contrast-enhanced ultrasound (CEUS) for differentiating malignant from benign focal liver lesions (FLLs) and for diagnosing different FLL types. CEUS performed in 14 Romanian centers was prospectively collected between February 2011 and June 2012. The inclusion criteria were: age > 18 years; patients diagnosed with 1 - 3 de novo FLLs on B-mode ultrasound; reference method (computed tomography (CT), magnetic resonance imaging (MRI) or biopsy) available; patient's informed consent. FLL lesions were characterized during CEUS according to the European Federation of Societies for Ultrasound in Medicine and Biology guidelines. For statistical analysis, indeterminate FLLs at CEUS were rated as false classifications. A total number of 536 cases were included in the final analysis, 344 malignant lesions (64.2 %) and 192 benign lesions (35.8 %). The reference method was: CT/MRI - 379 cases (70.7 %), pathological exam - 150 cases (27.9 %) and aspiration of liver abscesses - 7 cases (1.4 %). CEUS was conclusive in 89.3 % and inconclusive in 10.7 % of cases. To differentiate between malignant and benign FLLs, CEUS had 85.7 % sensitivity, 85.9 % specificity, 91.6 % positive predictive value, 77.1 % negative predictive value and 85.8 % accuracy. The CEUS accuracy for differentiation between malignant and benign liver lesions was similar in tumors with diameter ≤ 2 cm and those with diameter > 2 cm. CEUS represents a useful method in clinical practice for differentiating between malignant and benign FLLs detected on standard ultrasonography, and the results of this study are in concordance with previous multicenter studies: DEGUM (Germany) and STIC (France).

Both interactive visualization and computational analysis methods are useful for data studies and an integration of both approaches is promising to successfully combine the benefits of both methodologies. In interactive data exploration and analysis workflows, we need successful means to quantitatively externalize results from data studies, amounting to a particular challenge for the usually qualitative visual data analysis. In this paper, we propose a hybrid approach in order to quantitatively externalize valuable findings from interactive visual data exploration and analysis, based on local linear regression models. The models are built on user-selected subsets of the data, and we provide a way of keeping track of these models and comparing them. As an additional benefit, we also provide the user with the numeric model coefficients. Once the models are available, they can be used in subsequent steps of the workflow. A model-based optimization can then be performed, for example, or more complex models can be reconstructed using an inversion of the local models. We study two datasets to exemplify the proposed approach, a meteorological data set for illustration purposes and a simulation ensemble from the automotive industry as an actual case study.

Introduction of contrast agents as microbubbles and to improve ultrasound examination techniques has increased the rate of detection and characterization of liver lesions. Contrast-enhanced ultrasonography (CEUS) is a relatively new method of exploring the liver and diagnosing focal liver lesions (FLL). The aim of this study is to determine the efficiency of microbubbles used for CEUS in managing patients detected in conventional ultrasonography with FLL. We examined 84 patients with FLL, detected on conventional ultrasonography (US), during October 2012-September 2015. We performed contrast-enhanced ultrasonography, using sulphur hexafluoride as a contrast agent, and contrast-enhanced MRI to set the diagnosis. For 37 patients (44.1%) CEUS showed a malignity pattern of enhancement (according to the EFSUMB - European Federation of Societies for Ultrasound in Medicine and Biology- Guidelines 2012), while for 54 (64.3%) patients MRI set the diagnosis of malignity. CEUS detected fewer malignant lesions than MRI, in 20.1% of the cases MRI set de diagnosis. We need further studies in order to improve the quality of CEUS images and technique.

to assess the role of contrast-enhanced ultrasound (CEUS) in the characterization of focal liver lesions (FLLs) incidentally discovered but indeterminate at gray-scale ultrasound (US). one hundred forty-two consecutive patients with 174 FLLs (169 benign and 5 malignant) incidentally discovered but indeterminate at gray-scale US, underwent CEUS after the administration of SonoVue. Two readers independently reviewed CEUS scans and: (1) classified each lesion as malignant or benign on a 5-point scale of confidence by means of definite diagnostic criteria; (2) provided if possible a specific diagnosis; (3) were requested if further imaging was needed for lesion characterization. Sensitivity, specificity, and areas under the receiver-operating characteristic curve (Az) as well as interobserver agreement were calculated. at CEUS, both readers correctly differentiated benign from malignant lesions in 168 of 174 (96.5%) cases (P < 0.0001). A specific correct diagnosis was provided in 123 of 174 (70.7%) and 127 of 174 (72.9%) cases for reader 1 and 2, respectively (P < 0.0001). A further imaging study to characterize the lesion after CEUS was requested in 67 cases (38.5%) for reader 1 (P < 0.001) and 46 cases (26.4%) for reader 2 (P < 0.001). Receiver-operating characteristic analysis after CEUS revealed Az value of 1 for both readers and sensitivity and specificity values of 100% and 97.04% for reader 1 and 100% and 96.45 for reader 2 respectively (P < 0.0001). Inter-reader agreement at CEUS was good (weighted k = 0.779). CEUS improves the diagnostic performance of radiologists in the characterization of indeterminate FLLs incidentally discovered at US and reduces the need for further radiologic work-up.

Objective To assess the diagnostic performance of contrast-enhanced ultrasound in characterization of focal liver lesions after liver transplantation in comparison with baseline ultrasound.Methods Sixty-eight patients with focal liver lesions after liver transplantation were examined by baseline and contrast-enhanced ultrasound.Two independent investigators with different experience reviewed the images of baseline and contrast-enhanced ultrasound.The diagnostic performances were evaluated using sensitivity，specificity and accuracy.The interobserver agreement was analyzed.Results The sensitivity and accuracy for both investigatorswith different experience improved significantly after reviewing contrast-enhanced ultrasound(all P<0.05).There was greater improvement in inexperienced investigator compared with experienced investigator.A better interobserver agreement was achieved after reviewing contrast-enhanced ultrasound(к=0.632 at baseline ultrasound versus к=0.931 at contrast-enhanced ultrasound).Conclusions Contrast-enhanced ultrasound improves the diagnostic performance in focal liver lesions for discrimination between malignancy and benignity after liver transplantation. Key words: Ultrasonography; Microbubbles; Liver transplantation; Liver diseases

Contrast-Enhanced Ultrasound (CEUS) is a widespread method for non-invasive diagnosis of Focal Liver Lesions (FLLs). In this paper, an automatic classification algorithm of FLLs based on CEUS imaging is proposed. Firstly, from obtained dynamic CEUS videos of hepatic, Time Intensity Curves (TICs) are extracted. Then TICs' parameters: Peak, TP, Sharpness and AUC are calculated. Both TICs and their parameters are regarded as features in our method. Finally, based on these exeracted features, a Kernel Sparse Representation based Classification (KSRC) algorithm is employed to classify benign FLLs and malignant FLLs. Experimental results show that accuracy, sensitivity and specificity of our proposed method are 98.89%, which outperforms other similar methods.

US-guided percutaneous biopsy of focal liver lesions (FLL) is a classic interventional procedure performed by almost all radiology units. Typically, an incidental focal finding on US or a focal indeterminate lesion diagnosed on CT, MRI or PET/CT is referred for US-guided biopsy for final diagnosis. The introduction of microbubble US contrast agents has overcome some of the limitations of standard US in diagnosing FLLs by displaying the microvasculature together with the US morphology, which has increased both the sensitivity and the specificity. The combination of CEUS and intervention is facilitated by newer US equipment providing split-screen mode, which displays the CEUS mode alongside the standard US mode simultaneously on a single monitor. The puncture line is displayed in both modes as well as on the monitor. The interventional device (i. e., biopsy needle) is typically best visualized in the standard US mode, while the characteristic tissue pattern in an FLL is typically best visualized in CEUS mode. There are 3 main categories in which CEUS has an impact on US-guided biopsy of FLLs: • CEUS improves the visualization of FLLs • CEUS improves the quality of the biopsy specimen from an FLL • CEUS reduces the need for US-guided biopsy of an FLL In the two first categories, CEUS is utilized simultaneously with US-guided biopsy to ensure correct needle targeting. In the last category, US-guided biopsy of the FLL becomes superfluous as a result of the CEUS examination.

To compare the features of focal liver lesions in the arterial phase on contrast-enhanced ultrasonography (CEUS) and contrast-enhanced computed tomography (CECT). A total of 38 lesions in 29 patients with focal liver lesions (FLL) were examined with CEUS and CECT. The characteristics of the enhancement were determined, especially in the early arterial phase (0~25 s). The enhancement of FLL in CEUS and CECT graded as follows: grade 0 - no enhancement; grade I - peripheral enhancement or spotty enhancement at the center; grade II - spoke-like, honeycomb-like or heterogeneous enhancement; grade II - entire enhancement. On CEUS, the arriving time within 25 s was found in 36 out of 38 lesions (94.73%) and the peak time within 25 s in 29 lesions (76.32%). The number of grade II-III FLL was 25 (65.79%) on CEUS, and 13 (34.21%) on CECT showing a significant difference (p < 0.05). Compared with CECT, CEUS plays an important role in the diagnosis of FLL with enhancement in the early arterial phase (< 25 s).

Contrast-enhanced ultrasound (CEUS) utilization is expanding rapidly, particularly in children, in whom the modality offers the important advantages of dynamic evaluation of the vasculature, portability, lack of ionizing radiation, and lack of need for sedation. Accumulating data establish an excellent safety profile of ultrasound contrast agents (UCAs) in children. Although UCAs have been FDA-approved only for IV use in children for characterizing focal liver lesions and for use in children during echocardiography, off-label applications are expanding the diagnostic potential of ultrasound. Focal liver lesion evaluation is the most common use of CEUS, and the American College of Radiology Pediatric LI-RADS Working Group recommends including CEUS for evaluation of a newly discovered focal liver lesion in many circumstances. Data also support the role of CEUS in hemodynamically stable children with blunt abdominal trauma, and CEUS is becoming a potential alternative to CT in this setting. Additional potential applications that require further study include evaluation of pathology in the lung, spleen, brain, pancreas, bowel, kidney, female pelvis, and scrotum. This article explores the implementation of CEUS in children, describing basic principles of UCAs and CEUS technique and summarizing current and potential IV diagnostic applications based on pediatric-specific supporting evidence.