Conventional ultrasound(US) plays an important role in check-up, while contrast-enhanced ultrasound(CEUS) is a valuable tool for distinguishing tumor characteristics and guiding subsequent diagnosis and treatment. We present a rare case of duodenal neuroendocrine neoplasms (NENs) with liver metastasis in a young male, whose liver masses were detected by US during a check-up and then subsequently underwent Sonazoid-CEUS examination in the outpatient department. The lesions in the liver showed rapid hyper-enhancement in the arterial phase followed by early washout in the portal venous phase, finally showing a defect in the Kupffer phase, which strongly suggested metastases. The patient was promptly admitted for further examination, leading to a timely diagnosis of duodenal NENs with liver metastasis. This case highlights the importance of US and CEUS in asymptomatic liver masses in young patients.

Extramedullary hematopoiesis (EMH) is a rare condition where hematopoietic tissue forms outside the bone marrow. We present a case of a patient with long-standing myelofibrosis and thalassemia, diagnosed with intrahepatic EMH (IEMH) through surgical pathology. This case describes its etiology, pathogenesis, and the causes of misdiagnosis, mainly focusing on the characteristics of contrast-enhanced ultrasound (CEUS) and magnetic resonance imaging (MRI) of IEMH. The MRI manifestations of IEMH are diverse due to differences in the age and activity of the lesions. Notably, it provides the first description of IEMH's enhancement pattern on CEUS, a potential unique imaging feature of this condition.

Transarterial chemoembolization (TACE) is a well-established treatment for intermediate-stage hepatocellular carcinoma (HCC), shown through randomized trials to improve survival compared to supportive care in patients with large, unresectable tumors who are not candidates for liver transplantation or local ablation. As the most commonly used transarterial intervention, TACE is also employed to downstage advanced HCC, allowing certain patients to become eligible for orthotopic liver transplantation under the Milan criteria. Despite its widespread use, variability in therapeutic outcomes highlights the need for improved procedural guidance. Recent advancements in intra-arterial contrast-enhanced ultrasound (IA CEUS) offer new opportunities to enhance TACE precision with real-time imaging that provides superior visualization of tumor vasculature and chemoembolic agent distribution. This review explores the role of IA CEUS in refining TACE for HCC, emphasizing its potential to increase intraprocedural accuracy and reduce the risk of incomplete tumor embolization. The enhanced spatial resolution of IA CEUS enables real-time tracking of embolic agent dispersion within tumor vessels, which could improve therapeutic efficacy by ensuring complete tumor targeting and minimizing non-target embolization. Additionally, IA CEUS may decrease procedural complications by allowing dynamic adjustment of embolic delivery based on real-time imaging feedback. By reviewing existing evidence on IA CEUS applications in TACE, this article highlights the modality's potential to transform treatment protocols, improve outcomes, and expand the patient population eligible for TACE.

Despite growing clinical use of contrast-enhanced ultrasound (CEUS), inconsistency remains in the modality's role in clinical pathways for hepatocellular carcinoma (HCC) diagnosis and management. This AJR Expert Panel Narrative Review provides practical insights on the use of CEUS for the diagnosis of HCC across populations, including individuals at high risk for HCC, individuals with metabolic dysfunction-associated steatotic liver disease, and remaining individuals not at high risk for HCC. Considerations addressed with respect to high-risk patients include CEUS diagnostic criteria for HCC, use of CEUS for differentiating HCC from non-HCC malignancy, use of CEUS for small (≤2 cm) lesions, use of CEUS for characterizing occult lesions on B-mode ultrasound, and use of CEUS for indeterminate lesions on CT or MRI. Representative literature addressing the use of CEUS for HCC diagnosis as well as gaps in knowledge requiring further investigation are highlighted. Throughout these discussions, the article distinguishes two broad types of ultrasound contrast agents used for liver imaging: pure blood-pool agents and a combined blood-pool and Kupffer-cell agent. Additional topics include the use of CEUS for treatment response assessment after nonradiation therapies and implications of artificial intelligence technologies. The article concludes with a series of consensus statements from the author panel.

Access to healthcare services was significantly restricted during the COVID-19 pandemic, leading to changes in the management of hepatocellular carcinoma (HCC). However, limited research has examined how these changes evolved post-pandemic. This study evaluated the impact of the pandemic at a tertiary center in Romania, focusing on diagnosis rates, treatments, and survival outcomes.

A retrospective study conducted at Timișoara County Hospital divided patients into three equal cohorts of 23 months each: the pre-pandemic period (PreP: 1 May 2018-31 March 2020), the pandemic period (PandP: 1 April 2020-28 February 2022), and the post-pandemic period (PostP: 1 March 2022-31 January 2024). Newly diagnosed HCC cases were evaluated for the tumor stage, biological markers, and treatment received during each period. A survival census was conducted nine months after the diagnosis.

During the PandP and PostP periods, the numbers of newly diagnosed HCC cases decreased to 58 cases (p < 0.001) and 64 cases (p < 0.005), respectively, representing reductions of 38.3% and 31.9% compared to the PreP period, which had 94 cases. The proportion of patients in the BCLC-B stage increased from 31.9% in the PreP period to 50% during the PandP period (p = 0.0401), with fewer BCLC-A-0 cases (17% vs 5.1%; p = 0.059) during PandP. The tumor characteristics, BCLC classification, and TNM staging showed no significant differences between the PreP and PostP periods. Systemic therapy was the most commonly used treatment (39.7-50%). No significant differences were observed across treatment types when comparing all three periods (p > 0.05). The median follow-up times in the PreP, PandP, and PostP periods were 157.5, 159.5, and 183.5 days, respectively, with no statistically significant differences. The survival curve showed no statistically significant differences in survival between the groups at the nine-month follow-up (p > 0.05).

The COVID-19 pandemic decreased HCC diagnoses, with only a partial rebound in the PostP period that did not reach PreP levels. While the PandP period showed worsening BCLC staging and an increase in tumor numbers, the tumor stage and treatment in the PostP period were similar to those in the PreP period. Similarly, the nine-month survival rates remained similar across all three periods.

To develop a model combining contrast-enhanced ultrasound (CEUS) and ethoxybenzyl-enhanced magnetic resonance imaging (EOB-MRI) for predicting microvascular invasion (MVI) in solitary hepatocellular carcinoma (HCC) ≤5 cm.

Patients between December 2019 and May 2024 in one center were retrospectively enrolled and randomly divided into the training cohort and internal validation cohort in a ratio of 7:3. Patients in a separate center were enrolled between January 2022 and December 2023 to be included as the external validation cohort. CEUS and EOB-MRI image features were extracted and used to develop models in the training cohort, and verified in the two validation cohorts. The predictive accuracy and clinical utility of models were evaluated using area under receiver operating characteristic curve (AUROC), Brier score, calibration plot and decision curve analysis (DCA). Net reclassification index (NRI) and integrated discrimination improvement (IDI) were used to compare different models.

From the two centers a total of 493 patients, of which 134 were MVI positive, were evaluated. The CEUS+EOB model included seven image features and showed better discrimination ability than the individual CEUS/EOB-MRI model, with AUROCs of 0.92, 0.94, and 0.90 in the training cohort and two validation cohorts, respectively (p<0.05). The lowest Brier score of the combined model indicated the highest predictive precision. DCA also showed that the combined model added more net benefits. Both the NRI and IDI values >0 indicated that the combined model had significantly positive improvement (p<0.05).

The CEUS+EOB model was developed to assist clinicians in evaluating MVI in solitary HCC ≤5 cm.

Ultrasound molecular imaging is an innovative imaging modality that combines ultrasound with molecular probes to observe live biological processes at the cellular and molecular levels. C-X-C chemokine receptor type 4 (CXCR4) is a specific target in liver tumors and plays a crucial role in promoting tumor growth, invasion, metastasis, and angiogenesis. This study pioneered the use of CXCR4-targeted ultrasound molecular imaging for visualized antitumor therapy and investigated the potential of CXCR4-targeted microbubbles (MBs) in sensitizing liver tumor treatment. CXCR4-targeted MBs demonstrated high ligands conjugation efficiency to vascular endothelial cells (99.77 ± 0.15 %) and significantly inhibited the migration and invasion of Hepa1-6 cells. Molecular CEUS imaging results indicated that the MBs carrying LFC131 peptides facilitated site-specific recognition in BALB/c mice bearing Hep G2 tumors. After the 2-week of chemotherapy, ultrasound molecular imaging signals were significantly reduced in liver cancer when using CXCR4-targeted MBs compared to the SonoVue group which were corroborated by quantitative immunohistochemical grading of CXCR4 expression. In liver cancer immunotherapy, the anti-PD-L1 mAb + CXCR4-targeted MBs group yielded a remarkable tumor inhibition rate (94.6 %) with increased CD8+ T-cell infiltration and decreased FOXP3+ regulatory T cells. Bulk RNA-seq analysis and animal experiment confirmed that anti-PD-L1 mAb combined with CXCR4-targeted MBs effectively induced a robust immune response in liver cancer. These findings establish a solid foundation for future molecular CEUS imaging applications and the development of sensitization strategies for liver cancer therapy. STATEMENT OF SIGNIFICANCE: Ultrasound molecular imaging plays a pivotal role in advancing precision medicine by optimizing tumor diagnosis and treatment. This study pioneers ultrasound molecular imaging in liver tumor therapy using CXCR4-targeted microbubbles (MBs) conjugated with LFC131 peptides. Achieving 99.77 % ligand binding efficiency, the CXCR4-targeted MBs group suppressed tumor migration and enabled precise molecular imaging validated by immunohistochemistry. Moreover, the integration of CXCR4-targeted MBs with anti-PD-L1 immunotherapy resulted in a remarkable tumor inhibition rate of 94.6 %, accompanied by increased CD8+ T cells and decreased FOXP3+ regulatory T cells. These findings underscore the dual role of CXCR4-targeted MBs in both imaging and enhancing chemotherapy/immunotherapy, establishing a foundational framework for the future advancement of molecular imaging-guided liver cancer treatment.

To develop and validate an automated deep learning-based model for focal liver lesion (FLL) segmentation in a dynamic contrast-enhanced ultrasound (CEUS) video.

In this multi-center and retrospective study, patients with FLL who underwent dynamic CEUS exam were included from September 2021 to December 2021 (model development and internal test sets), and from March 2023 to May 2023 (external test sets). A bi-modal temporal segmentation network (BTS-Net) was developed and its performance was evaluated using Dice score, intersection over union (IoU) and Hausdorff distance, and compared against several segmentation methods. Time-intensity curves (TICs) were obtained automatically from BTS-Net and manually de-lineated by an experienced radiologist, and evaluated by intra-class correlation and Pearson correlation co-efficients. Multiple characteristics were analyzed to evaluate the influencing factors of BTS-Net.

A total of 232 patients (160 men, median age 56 y) with single FLL were enrolled. BTS-Net achieved mean Dice scores of 0.78, 0.74 and 0.80, mean IoUs of 0.67, 0.62 and 0.68, and mean Hausdorff distances of 15.83, 16.01 and 15.04 in the internal test set and two external test sets, respectively. The mean intra-class correlation and Pearson correlation co-efficients of TIC were 0.89, 0.92 and 0.98, and 0.91, 0.93 and 0.99, respectively. BTS-Net demonstrated a significantly higher mean Dice score and IoU in large (0.82, 0.72), homogeneous positive enhanced (0.81, 0.70) or stable (0.81, 0.70) lesions in pooled test sets.

Our study proposed BTS-Net for automated FLL segmentation of dynamic CEUS video, achieving favorable performance in the test sets. Downstream TIC generation based on BTS-Net performed well, demonstrating its potential as an effective segmentation tool in clinical practice.

Ultrasound diagnostics is a widely used, radiation-free, cost-effective, and bedside-applicable imaging technique. Given its numerous advantages and broad application, it appears reasonable to integrate practical use and theory into medical education at an early stage. Since the content of student ultrasound courses varies significantly on an international scale, the aim of this paper is to establish foundations for a more standardized approach to student's ultrasound education (SUSE) especially with focus on abdominal ultrasound. This review examines to what extent measurements can be effectively incorporated into student ultrasound training and under which conditions the teaching of pathologies should be included in these courses. Additionally, the handling of false-positive and false-negative findings in student training is discussed. Considering the growing relevance of interventional ultrasound (INVUS), the paper further explores the extent to which interventional procedures should already be taught during SUSE.

With the rapid development of endoscopic ultrasound (EUS), diagnostic and therapeutic platforms have emerged that are applicable in hepatology. New tools such as EUS-guided portal pressure measurement (in combination with EUS-guided liver biopsy) or EUS-guided variceal obliteration using coils and glue present attractive procedures that can potentially overcome the limitations of current gold standards. In this review article, we provide an overview of these new 'endo-hepatology' techniques and highlight their current role in the treatment of liver diseases.

Ultrasound contrast agents (UCAs) are microbubbles comprising an inert gas core stabilized by an encapsulating shell, which serves to increase the signal-to-noise ratio of blood-to-tissue in diagnostic ultrasound imaging. More recently, research has investigated the use of UCAs to combine both diagnostics and therapeutic outcomes in an amalgamated approach, designated 'theranostics.' Two examples of theranostic based approaches include the use of super-resolution imaging with ultrasound localized microscopy (ULM) and ultrasound-mediated drug delivery (UMDD). Both ULM and UMDD have been shown to have the potential to improve both patient care and clinical outcomes. Currently, there are 4 commercially available global UCAs licensed for clinical use. The physico-chemical properties of each of these UCAs influence its potential theranostic efficacy. Because of differences in their composition and/or manufacturing processes, each UCA has different characteristics that contribute to different in vivo resonance behavior, which in turn influences their effective clinical applications. This review highlights the key physico-chemical characteristic differences of the 4 commercially available contrast agents, with specific emphasis on their gaseous core, shell composition, and microbubble volume distribution, while providing novel insights into their benefits for supporting emerging clinical technologies, specifically ULM and UMDD.

In all imaging methods, including contrast-enhanced ultrasound (CEUS), enhancement in the late phase (LP) is an important criterion for differentiating between benign and malignant focal liver lesions (FLLs). In general, malignant liver lesions are characterized by hypoenhancement and washout in the LP. A lesion with LP hyperenhancement or isoenhancement in the non-cirrhotic liver is usually benign. However, LP hypoenhancement in benign lesions is not so rare, and is even normal and the standard for some lesions, and there are exceptions for each tumor entity that can represent a diagnostic challenge. Knowing these contrast patterns and exceptions is key for correct diagnosis and patient management. The following narrative review describes the contrast behaviors and the frequency of washout and LP hypoenhancement for common as well as rare benign liver lesions and analyzes its causes.

Contrast-enhanced US (CEUS) allows a detailed assessment of the tissue microvasculature after intravenous injection of contrast material. The use of CEUS also allows opacification of nonvascular hollow organs and fluid compartments after intracavitary instillation of dilute contrast material. This capability is far beyond that of grayscale and Doppler US techniques. The advantages of CEUS include its ease of use, high safety profile, and absence of ionizing radiation, making it an ideal tool for pediatric imaging. In 2016, the U.S. Food and Drug Administration approved CEUS for use in children for characterization of focal liver lesions and diagnosis of vesicoureteral reflux. Because the US contrast agent is distributed throughout the vascular pool, additional off-label imaging studies have focused on a variety of anatomic structures. This review of pediatric CEUS discusses the safety and technical aspects of CEUS, provides practical information on how to perform intravascular and intracavitary examinations, addresses the most common clinical applications of this method, and offers advice regarding the integration of CEUS into pediatric daily clinical practice.

Current literature on imaging characteristics of hepatic inflammatory pseudotumor (HIPT) is limited. This study aimed to analyze the contrast-enhanced ultrasound (CEUS) features in HIPT and compare them with contrast-enhanced computed tomography (CECT) and contrast-enhanced magnetic resonance imaging (CEMRI).

A total of 83 patients with histologically proven HIPT from two medical institutions were included in this study. All patients underwent CEUS within 1 week before surgery or biopsy. Some patients received additional CECT or CEMRI. B-mode ultrasound (BMUS) features, enhancement parameters of CEUS, CECT and CEMRI were analyzed. Chi-square test was used to compare the enhancement patterns and diagnostic sensitivity between CEUS and CECT/CEMRI.

On the BMUS, HIPT mainly appeared hypoechoic (83.5%, 66/79), irregular shapes (62.0%, 49/79), heterogeneous echogenicity (72.2%, 57/79), and unclear boundary (65.8%, 52/79). A total of 61.5% (51/83) lesions exhibited mild hyper- or iso-enhancement in the arterial phase (AP), 59.0% (49/83) lesions had internal nonenhanced areas, and most lesions (71.1%, 59/83) showed early wash-out (<60 seconds) on the CEUS. There were significant differences between CEUS and CECT/CEMRI in enhancement intensity of AP and wash-out pattern (P < .05). The sensitivity in the diagnosis of HIPT among the three had no statistical difference (P>.05).

The CEUS features of HIPT lesions typically include mildly hyper-enhanced or iso-enhanced in AP, rapid wash-out in PVP, and often small nonenhanced areas within the mass. Furthermore, the wash-out pattern of CEUS and CECT/CEMRI are inconsistent, more akin to cholangiocarcinoma. The diagnostic efficacy of the three modalities is similar.

This study aimed to identify the incidence of adrenal hemorrhage (AH) after OLT and to summarize the ultrasound (US) and contrast-enhanced ultrasound (CEUS) characteristics.

Patients with adrenal lesions after OLT at our hospital were retrospectively reviewed between January 2010 and November 2023. The reference diagnosis was defined on the basis of surgical data, computed tomography scans, and magnetic resonance imaging with at least 12 months of follow-up. The incidence of AH and the US and CEUS characteristics after OLT were analyzed and compared with those of adrenal metastases.

A total of 23 patients (1.2%) with AH and 7 patients (0.35%) with suprarenal metastases were assessed. Compared with metastases, hematomas had more inhomogeneous echotextures (57% vs. 0.00%, P = 0.010), hypoechoic or mixed-echoic patterns (96% vs. 71%, P = 0.022), and anechoic areas (52% vs. 0.00%, P = 0.024), and their echotextures varied more over time (65% vs. 0.14%, P = 0.031). CEUS was performed on 12 patients with AH and 2 patients with metastases. A "jet-like" contrast superflux was observed in one actively bleeding hematoma, whereas no enhancement was observed in any static hematoma (100%). However, adrenal metastases had a contrast-enhanced appearance in the early arterial phase, followed by fast washout in the late phase (100%), and the difference was statistically significant (P < 0.001).

The sonographic characteristics of AH after OLT vary over time. CEUS is recommended when adrenal lesions are detected, as CEUS can differentiate AH from metastases.

US-guided (Ultrasound-guided) percutaneous transthoracic core needle biopsy (CNB) is a favorable method for establishing the correct diagnosis of mediastinal masses. However, studies in this area are scant and often include small samples, thus making it difficult to provide robust evidence regarding the safety and efficacy of this procedure. Thus, we aimed to report on the 20 years of experience at our center with regard to US-guided CNB.We included all consecutive patients referred to our center to undergo US-guided percutaneous transthoracic CNB for a mediastinal mass between 1999 and 2022. Descriptive statistics were used to display data. A multivariate logistic regression analysis was used to inquire about predictors of diagnostic sampling.The final cohort included 140 patients with a median age of 37 years. In 20.7% of the cases, the mediastinal mass was an incidental finding. The parasternal approach was used most often. US-guided CNB was diagnostic in 84.3% of the patients and most of the diagnoses included hematological neoplasms. The reasons for non-diagnostic sampling included firm lesion consistency, low quantity of samples, and lesion necrosis. The parasternal approach resulted in an independent predictor of diagnostic sampling (AOR 4.16, 95% CI 1.14-15.23, p=0.031), while a bulky feature revealed only a trend for diagnostic sampling. One non-severe adverse event occurred, with spontaneous resolution.US-guided percutaneous transthoracic CNB is an effective and safe procedure that allows the diagnosis of mediastinal masses. The identification of patients that could benefit from this technique should be the next step in researching this topic.

Primary hepatic perivascular epithelioid cell tumor (PEComa) is an exceptionally rare mesenchymal neoplasm of borderline malignancy, with limited documentation of its contrast-enhanced ultrasound (CEUS) features in medical literature. In this context, we present a 53-year-old male patient without chronic liver disease, who exhibited a well-circumscribed hypoechoic left hepatic lobe mass on conventional ultrasonography. Subsequent CEUS demonstrated characteristics indicative of malignant tumors, with specific manifestations during the arterial phase, thereby informing clinical decision-making toward surgical resection. Histopathological confirmation of capsular-invasive PEComa underscores the utility of CEUS in characterizing such lesions, particularly in middle-aged patients with incidental solitary hepatic masses lacking predisposing risk factors. These findings advocate for the integration of CEUS into diagnostic algorithms to enhance specificity in atypical hepatic tumor evaluations.

Desmoplastic small round cell tumor (DSRCT) is a rare and highly aggressive malignant neoplasm, typically associated with poor prognosis. It predominantly affects adolescents and young males, with a lower incidence in pediatric populations. Due to its rarity, our understanding of DSRCT remains limited, with only a small number of case reports available. The clinical presentation is often non-specific and varies depending on the extent of tumor invasion. Diagnosis relies primarily on histopathological evaluation through biopsy. Although imaging studies contribute to the diagnostic process, they often lack specificity. Nonetheless, certain imaging features can aid in refining differential diagnoses and assessing disease severity. Moreover, minimally invasive, image-guided tissue sampling plays a critical role in confirming the diagnosis through pathological analysis.

A 7-year-old boy presented with abdominal distension and anorexia, without significant abdominal pain, fever, or jaundice. Physical examination revealed abdominal enlargement with hepatosplenomegaly. Laboratory tests showed abnormal liver function (AST 128 U/L, ALP 648 U/L, GGT 885 U/L) and an elevated CA-125 level (170 U/ml). An abdominal CT scan performed at a local hospital identified multiple round, low-density lesions in the liver, suggestive of echinococcosis. The patient was initially diagnosed with suspected echinococcosis and started on albendazole; however, his symptoms did not improve. Upon further evaluation at our institution, ultrasound imaging revealed multiple thick-walled, hyperechoic lesions in the liver with no significant blood flow signals. Contrast-enhanced ultrasound demonstrated that the solid components of the lesion exhibited significant enhancement during the early arterial phase, with rapid attenuation during the early portal venous phase. A metastatic malignant tumor was suspected, prompting a percutaneous biopsy under real-time enhanced ultrasound guidance. Histopathological examination revealed small round tumor cells infiltrating adjacent tissues. Fluorescence in situ hybridization (FISH) confirmed the diagnosis of DSRCT, based on the presence of an EWSR1-WT1 rearrangement. The patient subsequently underwent multimodal treatment, including chemotherapy and radiation therapy, and achieved disease-free survival at the six-month follow-up.

Traditional ultrasound is a convenient, real-time, non-invasive, and radiation-free diagnostic tool, making it particularly well-suited for the diagnosis, screening, and clinical follow-up of focal liver lesions (FLLs) in pediatric patients. This modality enables real-time evaluation of the number, size, location, and morphology of FLLs while assisting in the differential diagnosis. Moreover, it facilitates the assessment of liver parenchyma involvement and portal vein structures. Color Doppler imaging provides valuable insights into the vascular characteristics of tumors, while contrast-enhanced ultrasound (CEUS) agents allow for real-time observation of dynamic tumor perfusion patterns, further refining differential diagnoses based on perfusion characteristics. Compared to the contrast agents used in CT or MRI-which may require sedation or carry risks of renal injury due to radiation exposure-ultrasound microbubble contrast agents are excreted via respiration and do not require sedation, making them especially suitable for pediatric patients. Additionally, ultrasound-guided biopsy is a well-established and reliable method for diagnosing liver lesions. However, the presence of extensive necrosis and the use of fine-needle biopsy can sometimes limit diagnostic accuracy. Incorporating CEUS before or during percutaneous biopsy can help optimize sampling site selection, thereby reducing the likelihood of false-negative results.

Bladder cancer's high mortality underscores the need for precise staging, especially to differentiate between nonmuscle invasive bladder cancer (NMIBC) and muscle invasive bladder cancer (MIBC) types. This prospective study evaluated the efficacy of contrast-enhanced ultrasound (CEUS) for preoperative staging, focusing on its ability to distinguish NMIBC from MIBC. Conducted from April 2020 to September 2021, the study involved 163 patients (median age: 64.0 years; 137 males, 26 females), with 133 NMIBC (81.6%) and 30 MIBC (18.4%). Each patient underwent CEUS followed by transurethral resection of bladder tumor or radical cystectomy. CEUS demonstrated high diagnostic accuracy in determining muscle invasion status (sensitivity 83.3%, specificity 92.5%, accuracy 90.8%, area under the receiver operating characteristic curve [AUC] 0.88). Comparative analyses against MRI (AUC 0.77) showed CEUS outperforming in muscle invasion detection. Combining CEUS with MRI improved diagnostic accuracy, particularly when MRI vesical imaging reporting and data system score was 3 points. The combined approach achieved an AUC of 0.73, with sensitivity, specificity, and accuracy of 76.2, 70.2, and 71.6%, respectively. Thus, CEUS emerges as a valuable diagnostic tool for preoperative staging of bladder cancer, particularly in its role in assessing muscle invasion status and thereby aiding in clinical decision-making and intervention outcomes.

Hepatocellular carcinoma (HCC) is the most common form of hepatic malignancy, with high mortality rates recorded globally. Early detection through clinical biomarkers, medical imaging and histological assessment followed by rapid intervention are integral for positive patient outcomes. Although contrast-enhanced computed tomography scans and magnetic resonance imaging are recognised as the reference standard for the diagnosis and staging of HCC in international guidelines, ultrasound (US) examination is recommended as a screening tool for patients at risk. Contrast-enhanced US (CEUS) elevates the standard of an US examination using US contrast agents (UCAs), capable of diagnosing focal liver lesions with high efficacy. Most UCAs are purely intravascular, offering clinicians a dynamic representation of a lesions' arterial phase vascular kinetics, which is seldom seen in such detail during computed tomography or magnetic resonance imaging assessments. Despite its benefits, there is incongruity between international societies on the role of CEUS in the HCC clinical pathway. The transient nature of pure blood-pool agents is suggested to be insufficient to justify CEUS as a primary modality due to the inability to consistently perform whole liver imaging, alongside disputes regarding its capabilities to differentiate HCC from intrahepatic cholangiocarcinoma. A sinusoidal phase UCA affords clinicians the opportunity to perform whole liver imaging through Kupffer cell uptake in addition to visualising lesion vascular kinetics in the arterial and portal venous phases. Therefore, the purpose of this review was to examine the role of CEUS in the HCC clinical pathway in its current practice and observe how a Kupffer cell sinusoidal phase UCA may supplement contemporary diagnostic techniques through a multi-modality, multi-agent approach.

This study aims to evaluate the value of Kupffer phase imaging with Sonazoid-Contrast-Enhanced Ultrasound (CEUS) in differentiating atypical Hepatocellular Carcinoma (HCC) from Focal Nodular Hyperplasia (FNH), compared to the efficacy of Gadodiamide-Enhanced Magnetic Resonance Imaging (CEMRI).

We retrospectively reviewed a total of 56 focal liver lesions, comprising 36 atypical HCC and 20 FNH lesions, which were examined pre-operatively using both CEUS and CEMRI. Features were extracted from the images obtained from both modalities. The diagnostic performance of these features was evaluated using the Area Under the Receiver Operating Characteristic Curve (AUC).

In the multivariate analysis, HBsAg-positive status (OR = 8.395, p = 0.021) and hypo-enhancement in the Kupffer phase (OR = 5.276, p = 0.042) were identified as independent predictors of atypical HCC. The specificity and sensitivity of HBsAg-positive for diagnosing atypical HCC are 65.0 % and 91.7 %, respectively. The specificity and sensitivity of hypo-enhancement in the Kupffer phase for diagnosing atypical HCC are 95.0 % and 63.9 %, respectively. Significantly, by integrating CEUS diagnostic characteristics to distinguish atypical HCC from FNH, we attained a specificity of 100.0 %, a sensitivity of 63.9 %, and a diagnostic accuracy of 76.8 %. Similarly, the combination of CEMRI diagnostic features resulted in a specificity of 100.0 %, a sensitivity of 47.2 %, and an overall diagnostic accuracy of 66.1 %. CEUS's diagnostic accuracy is superior to CEMRI and this difference is statistically significant (P < 0.05).

Sonazoid-CEUS demonstrates significant clinical potential and is a viable tool for the differential diagnosis of atypical HCC and FNH.

To establish and validate a non-invasive deep learning (DL) model based on contrast-enhanced ultrasound (CEUS) to predict vessels encapsulating tumor clusters (VETC) patterns in hepatocellular carcinoma (HCC).

This retrospective study included consecutive HCC patients with preoperative CEUS images and available tissue specimens. Patients were randomly allocated into the training and test cohorts. CEUS images were analyzed using the ResNet-18 convolutional neural network for the development and validation of the VETC predictive model. The predictive value for postoperative early recurrence (ER) of the proposed model was further evaluated.

A total of 242 patients were enrolled finally, including 195 in the training cohort (54.6 ± 11.2 years, 178 males) and 47 in the test cohort (55.1 ± 10.6 years, 40 males). The DL model (DL signature) achieved favorable performance in both the training cohort (area under the receiver operating characteristics curve [AUC]: 0.92, 95% confidence interval [CI]: 0.88-0.96) and test cohort (AUC: 0.90, 95% CI: 0.82-0.99). The stratified analysis demonstrated good discrimination of DL signature regardless of tumor size. Moreover, the DL signature was found independently correlated with postoperative ER (hazard ratio [HR]: 1.99, 95% CI: 1.29-3.06, p = 0.002). C-indexes of 0.70 and 0.73 were achieved when the DL signature was used to predict ER independently and combined with clinical features.

The proposed DL signature provides a non-invasive and practical method for VETC-HCC prediction, and contributes to the identification of patients with high risk of postoperative ER.

This DL model based on contrast-enhanced US displayed an important role in non-invasive diagnosis and prognostication for patients with VETC-HCC, which was helpful in individualized management.

Preoperative biopsy to determine VETC status in HCC patients is limited. The contrast-enhanced DL model provides a non-invasive tool for the prediction of VETC-HCC. The proposed deep-learning signature assisted in identifying patients with a high risk of postoperative ER.

To analyze Necrotic Area Features of subpleural pulmonary lesions (SPLs) demonstrated by contrast-enhanced ultrasound (CEUS) and investigate their value in differentiating between malignant and benign SPLs.

Patients with SPLs who underwent CEUS at our hospital from January to May 2021. The following patient information was recorded: (i) age, (ii) sex, (iii) lesion size, (iv) lesion location, (v) size of necrotic areas and (vi) necrotic area morphology, including sieve-like necrosis, necrotic area with septal enhancement, necrotic area with annular enhancement margins, and necrotic area with burr-like enhancement margins. These parameters were analyzed using univariate and multivariate logistic regression. Subgroup analyses based on lesion size were further conducted using the collected data.

A total of 212 patients with 212 SPLs were enrolled, comprising 99 benign and 113 malignant cases. Significant differences were observed between malignant and benign groups in terms of age, sex, lesion size and necrotic area morphology (all, p < 0.05).

Necrotic area's features observed on CEUS were valuable for distinguishing between benign and malignant SPLs. Age, sex, lesion size and the presence of burr-like enhancement margins are identified as independent predictors of malignant lesions.

To investigate the relationship between the rim-like enhancement pattern on pre-ablation contrast-enhanced ultrasound (CEUS) of colorectal liver metastasis (CRLM) and the therapeutic efficacy of percutaneous microwave ablation (MWA).

Patients with CRLM underwent MWA and were evaluated using CEUS before ablation in our hospital between February 2020 and February 2023 were enrolled in this retrospective study. The enhancement patterns of CRLM were assessed by two radiologists and classified as rim-like enhancement and non-rim-like enhancement patterns. The therapeutic outcomes, including cumulative intrahepatic progression rate and early intrahepatic progression rate, were followed up and analyzed.

Overall, 50 patients with 121 nodules were enrolled. Rim-like enhancement pattern was observed in 18 patients (18/50, 36.0%). The cumulative intrahepatic progression rate was significantly higher in the rim-like enhancement group than the rate in the non-rim-like enhancement group (p = 0.022). The early intrahepatic progression rate in the rim-like enhancement group was also significantly higher than the rate in the non-rim-like enhancement group (12/17, 70.6% vs. 6/24, 25.0%, p = 0.005). The multivariable analysis demonstrated that the rim-like enhancement pattern of CRLM was a significant risk factor associated with early intrahepatic progression after MWA (p = 0.013).

Rim-like enhancement pattern on pre-ablation CEUS of CRLM was associated with a higher risk of intrahepatic progression after MWA.

To compare the diagnostic performance of CEUS-guided biopsy (CEUS-GB) and ultrasound-guided biopsy (US-GB) in evaluating abdominal and pelvic (abdominopelvic) neoplasms in paediatric patients.

Patients aged < 18 years with abdominopelvic tumours who underwent either CEUS-GB or US-GB between April 2005 and May 2022 were retrospectively evaluated. Tumours diagnosed as malignancies by pathology were considered true-positive findings. Benign lesions were identified by pathology or clinical follow-up of at least 6 months. The diagnostic performance of the two groups was compared using propensity score matching (PSM). Complications were also analysed.

The present study included 764 paediatric patients (437 boys; median age, 24 months; interquartile range, 10-60 months); 151 were in the CEUS-GB group, and 613 were in the US-GB group. The sample adequacy rate was 100% (151 of 151) for the CEUS-GB group, which was greater than the 97.4% (597 of 613) for the US-GB group (p < 0.001). The overall diagnostic accuracy of the CEUS-GB group and US-GB group was 98.7% (149 of 151) versus 97.3% (581 of 597) in the total cohort (p = 0.551) and 98.7% (149 of 151) versus 92.7% (140 of 151) in the PSM cohort (p = 0.020). Two patients (0.3%) in the US-GB group experienced complications (Common Terminology Criteria for Adverse Events (CTCAE), grade 1-2) correlated with the biopsy. No adverse reactions occurred in the CEUS-GB group.

CEUS-GB of abdominopelvic tumours in paediatric patients is an effective and safe procedure with greater diagnostic accuracy than US-GB, especially for tumours with necrotic areas.

Contrast-enhanced US-guided biopsy of solid abdominal and pelvic tumours in paediatric patients is an effective and safe procedure with greater diagnostic accuracy than US-guided biopsy, especially for tumours with necrotic areas.

Contrast-enhanced ultrasound (CEUS) may be superior to conventional ultrasound at guiding biopsy of abdominopelvic masses in paediatric patients. CEUS-guided core needle biopsy of abdominopelvic masses in children was safe and resulted in a diagnostic yield of 98.7%. CEUS guidance should be considered in this population when colour Doppler US is unable to determine a biopsy site.

To predict the degree of pathological differentiation of hepatocellular carcinoma (HCC) by quantitative analysis the correlation between the perfusion parameters of contrast-enhanced ultrasound (CEUS) and the pathological grades of HCC using VueBox® software.

We enrolled 189 patients who underwent CEUS and liver biopsy at our hospital from July 2019 to September 2024 and were pathologically confirmed with primary HCC. The Edmondson-Steiner pathological classification system was used as the gold standard for dividing the patients into the low-grade and high-grade groups. The patients were randomly divided into training set and testing set in a ratio of 7:3, in which the parameters of the training set were analyzed by univariate analysis and then stepwise regression to construct the prediction model, and the diagnostic efficacy of the validation model was evaluated by discrimination, calibration, and clinical applicability.

A total of 189 patients with primary hepatocellular carcinoma were enrolled, including 118 patients in the low-grade group and 71 patients in the high-grade group; they were randomly divided into training set of 128 patients and testing set of 61 patients. The prediction model was constructed by logistic regression in the training set, and the final model included three variables: mTTI, FT, and maximum diameter of a single lesion, resulting in the equation was Y = - 2.360 + 1.674 X 1 + 1.019 X 2 + 0.753 X 3 ( 2 ) + 1.570 X 3 ( 3 ) .The area under the ROC curve (AUC) of the training set was 0.831, with a sensitivity of 82.0% and a specificity of 79.5%; the area under the ROC curve (AUC) of the testing set was 0.811, with a sensitivity of 81.0% and a specificity of 70.0%.

The regression model constructed by combining multiple parameters can effectively improve the diagnostic performance of CEUS in predicting the pathological differentiation grade of HCC, thus providing a clinical basis and empirical support for the use of CEUS as a diagnostic imaging method for this disease.

To investigate Sonazoid contrast-enhanced ultrasound (CEUS) features of intrahepatic cholangiocarcinoma (ICC) based on liver backgrounds and tumor sizes.

A retrospective analysis was conducted on patients with histopathologically diagnosed ICC at two centers. Patients underwent Sonazoid CEUS examination at a dose of 0.0165 mL/kg before surgery or biopsy. Continuous imaging was recorded for the first 70 s, followed by intermittent scanning every 15-20 s for 5 min, with a Kupffer phase captured after an 8-min delay. Patients were categorized by liver backgrounds and tumor sizes. Two ultrasound experts evaluated the enhancement patterns of ICCAs during the arterial, portal, delayed, and Kupffer phases according to current guidelines.

From February 2019 to July 2022, a total of 85 ICC lesions were included. ICCs were categorized into normal liver (n = 24), chronic liver disease with fibrosis (n = 40), and cirrhosis (n = 21) groups based on different liver backgrounds, and into groups measuring ≤30 mm (n = 22), 31-50 mm (n = 32), and >50 mm (n = 31) based on tumor sizes. Most ICCs in liver fibrosis or liver cirrhosis tended to show non-rim enhancement in arterial phase (p = 0.022) and relatively later washout (39.9 ± 8.5 s vs. 39.7 ± 13.0 s) compared with those on a normal liver background (28.1 ± 5.6 s) (p < 0.001). Based on CEUS Liver Imaging Reporting and Data System, the diagnostic performance of LR-M criteria showed an accuracy of 100% in our high-risk populations. ICCs of ≤30 mm more commonly showed non-rim enhancement in arterial phase (p = 0.003) and relatively later washout (41.3 ± 12.5 s) compared with larger ICCs (p = 0.046). In the Kupffer phase, all ICCs showed marked washout with sharp margin delineation on Sonazoid CEUS, regardless of liver backgrounds and tumor sizes.

Sonazoid CEUS features of ICCs differ according to different liver backgrounds and tumor sizes. Arterial phase non-rim enhancement and relatively later washout were more commonly observed in ICCs on liver fibrosis or cirrhosis background or smaller ICCs (≤30 mm).

To evaluate the response to neoadjuvant therapy in patients with colorectal liver metastases (CRLMs) using ultrasound(US) and contrast-enhanced ultrasound(CEUS), with correction to the tumor regression grade (TRG) of pathological results.

This study included patients with resectable CRLMs admitted from February to December 2022. After at least 4 cycles neoadjuvant therapy, all the patients received US and CEUS examinations within two weeks before hepatectomy. CEUS clips were postprocessed with color parameter imaging (CPI) and microflow imaging (MFI) analysis. Logistic regression analyses were used to develop an evaluation Nomogram. Ultrasound-based model was constructed to discriminate between the response (TRG1/2/3) and nonresponse (TRG4/5) groups at the lesion level. The model's predictive ability was evaluated using the C index and calibration curve, with decision curve analysis assessing the Nomogram's added value.

The study analyzed 105 CRLM lesions (the lesion with the highest diameter analyzed for each patient), with 43.8% showing a response to therapy. Univariate analysis identified calcification on US (p = 0.039), CEUS enhancement degree (p < 0.001), CEUS enhancement pattern (p<0.001), CEUS washout type (p < 0.001), CEUS necrosis (p < 0.001), CPI feeding artery (p = 0.003) and MFI pattern (p < 0.001) were significantly associated with TRG. The multivariate analysis showed CEUS enhancement pattern (p = 0.026), CEUS washout type (p = 0.018) and CEUS necrosis (p = 0.005) were independently associated with the neoadjuvant therapy response. A Nomogram with the three independent predictors was developed, with an AUC of 0.898.

The ultrasound-based model provided accurate evaluation of pathological tumor response to preoperative chemotherapy in patients with CRLM, and may help to decide the individualized treatment strategy.

In patients with chronic inflammatory bowel disease (IBD), endoscopic techniques (including capsule techniques and balloon enteroscopy for the small intestine), ultrasound (US), computed tomography (CT) and magnetic resonance imaging (MRI) are primarily used as often complementary imaging techniques. Radiation exposure needs to be kept in mind when using CT and conventional X‑ray-techniques. Therefore, most importantly, ultrasound and MRI have changed the routine diagnostics of intestinal diseases. US, CT and MRI not only assess the lumen but, similarly importantly, also the wall and the surrounding structures of the gastrointestinal tract. Furthermore, functional processes can be visualized and provide important information about passage and perfusion, which is mainly true for real-time ultrasound. CT and MRI are usually carried out with the use of contrast agents as contrast-enhanced CT (CECT) and contrast-enhanced MRI (CEMRI). Ultrasound is performed conventionally or with intravascular (CEUS) and/or extravascular intracavitary contrast agent application (icCEUS). This article provides an overview of the current significance of the mentioned imaging procedures in patients with IBD and discusses the typical indications.

Background: Contrast-enhanced ultrasound (CEUS) has become the preferred method for many clinicians in evaluating focal liver lesions (FLLs) initially identified through standard ultrasound. However, in clinical practice, certain lesions may deviate from the typical enhancement patterns outlined in EFSUMB guidelines. Methods: This study aims to assess FLLs that remained inconclusive or misdiagnosed after CEUS evaluation, spanning eight years of single-center experience. Following CEUS, all FLLs underwent secondary imaging (CT, MRI) or histopathological analysis for diagnostic confirmation. Results: From the initial 979 FLLs, 350 lesions (35.7%) were either inconclusive or misdiagnosed by CEUS, with hepatocellular carcinoma (HCC) and liver metastases constituting the majority of these cases. The most frequent enhancement pattern in inconclusive lesions at CEUS was hyper-iso-iso. Factors such as advanced liver fibrosis, adenomas, and cholangiocarcinoma were significantly associated with higher rates of diagnostic inaccuracies. Conclusions: Advanced liver fibrosis, adenomas, and cholangiocarcinoma were significantly associated with increased diagnostic challenges, emphasizing the need for supplementary imaging techniques.

To evaluate the diagnostic value of contrast-enhanced ultrasound (CEUS) in detecting tuberculous diaphragmatic abscess (TDA) of the right diaphragm and provide a reference for its clinical diagnosis.

A retrospective analysis was conducted on 33 patients with right TDA confirmed via surgery and biopsy. The diagnostic accuracy of CEUS and routine ultrasound for detecting right TDA was compared.

Among the 33 right TDA cases, the lesions primarily exhibited mixed and low echogenicity, with an orientation parallel to the diaphragmatic surface. Eighteen patients (54.5%) demonstrated the characteristic "crocodile mouth sign." Heterogeneous enhancement was observed in most cases (24 patients) compared to homogeneous or no enhancement. The diagnostic accuracy of routine ultrasound for right TDA was 54.50% (18/33), whereas CEUS demonstrated a significantly higher accuracy of 78.78% (26/33) (χ2 = 4.364, P = 0.037).

CEUS provides valuable insights into the vascular characteristics of right TDA, with most cases showing mixed echogenicity and heterogeneous enhancement. The "crocodile mouth sign" was a distinctive feature, highlighting the utility of CEUS in improving diagnostic accuracy for right TDA.

Over the past two decades, contrast-enhanced ultrasound (CEUS) has been established as a method complementary to B-mode ultrasound and color Doppler sonography for diagnosing vascular liver pathologies and interventions.The objective of this review is to elucidate the application of CEUS in diagnosing vascular pathologies and interventional procedures.Considering the limitations of ultrasound, CEUS presents a similar alternative to other imaging modalities, such as computed tomography and magnetic resonance imaging, for evaluating vascular pathologies, guiding interventions, identifying complications, and assessing outcomes post intervention. Due to its widespread availability and the absence of radiation exposure, CEUS should be employed as a primary modality. · CEUS plays an important role in the detection of vascular liver pathologies.. · CEUS is helpful in characterizing vascular pathologies.. · CEUS is helpful in guiding interventions and identifying complications..

We hypothesized that contrast-enhanced ultrasound (CEUS) using a microbubble technique to quantify microvascular changes and Nakagami imaging for tissue characterization would provide a new approach for diagnosing and differentiating benign and malignant choroidal lesions.

Five patients with choroidal melanoma (CM) and five patients with choroidal hemangioma (CH) were selected. Definity®, which contains perflutren microbubbles, was administered as a slow IV bolus (1 ml). CEUS was performed for 1 min postinjection of the contrast agent with ultrasound radiofrequency data acquired from 10 s to 60 s. The contrast value was calculated for the whole tumor region. A gradient magnitude method was used for each postcontrast frames with 1-second interval, and the time-averaged value in pixel intensity gradient of postinjection frames was estimated and reported. Based on the Nakagami statistical distribution model, two Nakagami parameters, m and Ω, where m (shape parameter), representing tissue heterogeneity, and Ω (scale parameter), representing the average energy of backscattered signals, were studied.

CEUS analysis showed that the time-averaged estimated contrast was significantly higher (p = 0.008) for CH compared to CM. Furthermore, the time-averaged contrast within the normal choroidal region was significantly higher than the choroidal tumor region for both CH and CM (p = 0.001 for CH cases and p < 0.0001 for CM cases). Nakagami analysis showed that the m estimates were significantly higher (p = 0.032) for CH (m = 0.61) than for CM (m = 0.28), indicating that CH is a more heterogeneous tumor than CM. The Ω estimates were significantly higher (p = 0.0019) for CH (Ω = 0.15) compared to CM (Ω = 0.03). These results may be due to the more vascular structures in CH compared to CM.

Quantitative intensity-based perfusion analysis using CEUS and backscattering tissue analysis using Nakagami imaging can provide valuable insights to differentiate benign and malignant choroidal lesions.

Intravenous contrast-enhanced ultrasound (CEUS) is a rapidly evolving imaging technique that uses a microbubble contrast agent to enhance ultrasonographic images by augmenting characterization of blood vessels and organ perfusion. CEUS is considered as a useful problem-solving tool and as an indicated first-line imaging modality in select settings. CEUS technique has an inherent advantage over its predecessor B-mode and Doppler imaging. This article reviews different approved and off-label use of CEUS in the pediatric and adult population and also discusses Food and Drug Administration-approved contrast agents in the United States, their reported side effects, and ongoing efforts in the field.

Hepatocellular adenomas (HCA) are acquired focal liver lesions, that occur mainly in young-to-middle-aged women who are on long-term estrogen-containing contraceptives or young men after prolonged use of anabolic steroids. Furthermore, distinct underlying diseases, such as obesity, metabolic dysfunction-associated steatotic liver disease, glycogen storage disease, etc. are considered risk factors. The 2017 Bordeaux classification, in particular Nault et al, divided HCAs into eight subtypes according to their pheno- and genotypic characteristics. This includes HCAs with hepatocyte-nuclear-factor (HNF1-alpha mutation), HCAs with β-catenin mutation, and HCAs without either of these genetic mutations, which are further subdivided into HCAs with and without inflammatory cells. HCAs should no longer be classified as purely benign without histologic workup since three of the eight subtypes are considered high-risk lesions, requiring adequate management: malignant transformation of the pure (ßex3-HCA) and mixed inflammatory/β-catenin exon 3 (ßex3-IHCA) adenomas, as well as potential bleeding of the sonic hedgehog HCA and pure (ßex7/8-HCA) and mixed inflammatory/β-catenin exon 7/8 (ßex7/8-IHCA). Elective surgery is recommended for any HCA in a male, or for any HCA exceeding 5 cm. Although MRI can classify up to 80% of adenomas, if findings are equivocal, biopsy remains the reference standard for adenoma subtype.

Contrast-enhanced ultrasound (CEUS) is an advanced ultrasound (US) technique utilizing ultrasound contrast agents (UCAs) to provide detailed visualization of anatomic and vascular architecture, including the depiction of microcirculation. CEUS has been well-established in echocardiography and imaging of focal hepatic lesions and recent studies have also shown the utility of CEUS in non-hepatic applications like the urinary system. The updated guidelines by the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) from 2018 describe the use of CEUS for non-hepatic applications. CEUS' excellent safety profile and spatial resolution make it a superior modality to conventional US and is often comparable and even superior to CECT in some instances. In comparison to other cross-sectional imaging modalities such as CECT or MRI, CEUS offers a safe (by virtue of non-nephrotoxic US contrast agents), accurate, cost-efficient, readily available, and a quick means of evaluation of multiple pathologies of the urinary system. CEUS also has the potential to reduce the overall economic burden on patients requiring long-term follow-up due to its low cost as compared to CT or MRI techniques. This comprehensive review focuses on the applications of CEUS in evaluating the urinary system from the kidneys to the urinary bladder. CEUS can be utilized in the kidney to evaluate complex cystic lesions, indeterminate lesions, pseudotumors (vs solid renal tumors), renal infections, and renal ischemic disorders. Additionally, CEUS has also been utilized in evaluating renal transplants. In the urinary bladder, CEUS is extremely useful in differentiating a bladder hematoma and bladder cancer when conventional US techniques show equivocal results. Quantitative parameters of time-intensity curves (TICs) of CEUS examinations have also been studied to stage and grade bladder cancers. Although promising, further research is needed to definitively stage bladder cancers and classify them as muscle-invasive or non-muscle invasive using quantitative CEUS to guide appropriate intervention. CEUS has been very effective in the classification of cystic renal lesions, however, further research is needed in differentiating benign from malignant renal masses.

To enhance the accuracy of hepatocellular carcinoma (HCC) diagnosis using contrast-enhanced (CE) US, the American College of Radiology developed the CEUS Liver Imaging Reporting and Data System (LI-RADS). However, the system still exhibits limitations in distinguishing between HCC and non-HCC lesions.

To investigate the viability of employing machine learning methods based on quantitative parameters of contrast-enhanced ultrasound for distinguishing HCC within LR-M nodules.

This retrospective analysis was conducted on pre-treatment CEUS data from liver nodule patients across multiple centers between January 2013 and June 2022. Quantitative analysis was performed using CEUS images, and the machine learning diagnostic models based on quantitative parameters were utilized for the classification diagnosis of LR-M nodules. The performance of the model was assessed using the area under the receiver operating characteristic curve (AUC) and compared with the performance of four radiologists.