Dirk Andre Clevert

The present review of the most common liver lesions describes the possibilities for using the novel super-resolution contrast-enhanced ultrasound technique. There are advantages for visualizing the microvasculature and thus for the characterization of a vascular pattern: in the arterial phase as benign and regular or as malignant and irregular. In the case of hepatocellular carcinomas, small irregular focal lesions or signs of remaining tumor or early tumor recurrence after partial tumor resection or ablation can be identified. Benign tumors usually have a regular vascular pattern. Especially in the case of focal nodular hyperplasia (FNH), the regular vascular pattern can be clearly visualized on super-resolution imaging. In the case of malignant lesions, the technique can show the irregular neovascularization. The case studies relate to the most common liver lesion entities that can be detected and characterized in large clinical studies with high diagnostic certainty with dynamic contrast-enhanced ultrasound (CEUS).

Imaging during pregnancy presents unique challenges. Computed tomography (CT) is generally avoided due to fetal radiation exposure, and magnetic resonance imaging (MRI) may be limited by concerns regarding gadolinium-based contrast agents. As a result, ultrasound (US) remains the primary imaging tool during pregnancy. Contrast-enhanced ultrasound (CEUS) expands the diagnostic capabilities of conventional US by providing real-time vascular information comparable to contrast-enhanced CT or MRI. Importantly, microbubble contrast agents used in CEUS do not cross the placenta and have shown no fetal harm in clinical studies. Nevertheless, CEUS remains an off-label technique during pregnancy, underscoring the need for a comprehensive review of the available literature to assess its safety and clinical applications during pregnancy. This review summarizes the current evidence up to 2025 on the use of CEUS in pregnancy and highlights its clinical value with respect to evaluating acute and chronic maternal conditions – including oncologic, vascular, infectious, inflammatory, and other organ-specific pathologies – illustrated through representative case examples. Clinical studies, case reports, and international guidelines were analyzed with a focus on safety and diagnostic performance. Although still off-label, CEUS demonstrates an excellent safety profile and high diagnostic utility when clinically indicated in pregnancy. No maternal, fetal, or neonatal adverse effects have been reported, and no placental transfer of microbubbles has been demonstrated. CEUS enables high-resolution assessment of abdominal organs, vascular pathologies, and inflammatory or infectious changes, reducing the need for ionizing or gadolinium-based imaging. It represents a safe, effective, and radiation-free diagnostic alternative when conventional imaging is limited.

Background and Objective: Adverse pathology to high-risk prostate cancer (PCa) after radical prostatectomy (upgrading) poses a threat to risk stratification and treatment planning. The impact on sexual function, urinary continence, and health-related quality of life (HRQOL) remains unclear. Methods: From 2004 to 2024, 4189 patients with preop low-/intermediate-risk PCa (Gleason score 6 or 7a, PSA ≤ 20 ng/mL) underwent radical prostatectomy at our department and were analyzed. Primary endpoint was HRQOL, erectile function, and urinary continence. Secondary endpoint was rate of salvage therapies and biochemical-free survival. Propensity score matching was performed using “operative time”, “robot-assisted surgery”, “blood loss”, “nerve-sparing surgery”, “age”, and “BMI” to represent comparable surgical approach. Median follow-up was 39 months (Interquartile-range (IQR) 15–60). Key Findings and Limitations: Patients who were upgraded to high-risk PCa showed a higher rate of postoperative radiotherapy and androgen-deprivation therapy compared to patients who were not upgraded (21% vs. 7%, p < 0.001; 9% vs. 3%, p = 0.002). Five-year biochemical recurrence-free survival was 68% in the upgrading group vs. 84% in the no-upgrading group (p < 0.001). We saw no difference in patient-reported HRQOL, urinary continence, or erectile function. Multivariable analysis showed that postoperative upgrading was a significant risk for not achieving good overall HRQOL (OR: 0.77, 95% CI: 0.61–0.97, p = 0.028) during the follow-up. Conclusions and Clinical Implications: Although postoperative upgrading to high-risk PCa leads to worse oncologic outcomes and higher salvage therapy rates, this study indicates that its impact on health-related quality of life is minimal and should not deter a cautious approach to radical prostatectomy.

Introduction/Objective: Contrast-enhanced ultrasound (CEUS) is a promising modality for differentiating benign and malignant lesions in various organs, including the testis. Testicular tumors, common in young men, are often treated with radical orchiectomy, which can have significant consequences. This study aimed to analyze CEUS parameters and their association with malignant testicular tumors. Materials and Methods: Between May 2009 and September 2020, 342 patients with suspected testicular lesions underwent CEUS at a tertiary referral center. Multiparametric ultrasound, including B-mode, Color Doppler, CEUS, and elastography, was performed. Exclusion criteria were the absence of a testicular lesion in the CEUS examination. Histological results, CEUS parameters, and elastography data were analyzed, and statistical correlations were evaluated using chi-square and Mann–Whitney U tests, with multivariate logistic regression for significant findings. Results: Of the 342 patients, 114 (33.3%) had suspicious CEUS findings, and 84 underwent surgical exploration. Malignancy was confirmed in 48 cases (57.1%). The sensitivity and specificity of CEUS for detecting malignancy were 93.8% and 85.2%, respectively. Contrast enhancement was observed in 93.3% of malignant tumors, but not statistically significant compared to benign lesions (p = 0.107). However, elastography revealed higher tissue stiffness in 77.8% of malignant tumors versus 41.0% in benign lesions (p = 0.009). Multivariate analysis indicated that tissue stiffness was significantly associated with malignancy (HR 8.29, 95%CI 1.26–54.58, p = 0.028). Conclusions: CEUS is a valuable tool for testicular lesion evaluation, with elastography showing strong potential in predicting malignancy through tissue stiffness. However, contrast enhancement and “wash-in/-out” were not reliable malignancy indicators. Further research is needed to standardize CEUS and elastography techniques for routine clinical use.

Continuous-flow left ventricular assist devices have become an important treatment option for patients with advanced heart failure. However, adverse hemodynamic effects as consequence of an altered blood flow within the aorta and the aortic root remain a topic of concern. In this work, we investigated the influence of the outflow graft orientation on the hemodynamic profile and flow parameters within the thoracic aorta. Aortic models with different outflow graft orientations were designed and three-dimensional (3D) printed to mimic common implantation configurations and were integrated into a pulsatile mock circulatory flow loop. Assist device function was achieved using a rotary pump, replicating nonpulsatile, continuous support flows of 1–5 L/min. Flow velocity, wall shear stress, and pressure gradients were investigated for each configuration using sonography and four-dimensional (4D) flow magnetic resonance imaging. Mean wall shear stresses measured in 4D flow software were lowest for a graft inclination angle of 45°. Streamline visualization revealed areas of nonuniform, retrograde, and vortex flow in all models but most prominent for the aortic model with an outflow graft inclination of 60°. The insights gained from this research may aid in understanding clinical outcomes following assist device implantation and long-term mechanical circulatory support.

Objectives: To investigate the value of vascular morphology on high frame rate contrast-enhanced ultrasound (H-CEUS) and CEUS Li-RADS in predicting microvascular invasion (MVI), Ki-67 expression and recurrence of hepatocellular carcinoma (HCC). Methods: This retrospective study enrolled 78 patients with single HCC diagnosed by postoperative pathology between January 1, 2021, and June 30, 2022. All patients underwent ultrasound and H-CEUS examination before operation. H-CEUS image features and CEUS Li-RADS were compared in different MVI status and Ki-67 level. Multiple logistic regression analysis was performed to select independent variables for MVI. Differences in recurrence among different H-CEUS image features, MVI status and Ki-67 level were further analyzed. Results: Tumor shape, vascular morphology, LR-M category, necrosis and AFP level were different between the MVI-positive group and MVI-negative group (p < 0.05). Vascular morphology and LR-M category were independent risk factors related to MVI (p < 0.05). Vascular morphology was also different between the high Ki-67 expression group and low Ki-67 expression group (p < 0.05). Vascular morphology, MVI status and Ki-67 expression were different between the recurrence group and no recurrence group (p < 0.05). Conclusion: The vascular morphology of HCC on H-CEUS can indicate the risk of MVI status, Ki-67 expression and recurrence, which provides a feasible imaging technique for predicting the prognosis before operation. Critical relevance statement: H-CEUS shows the different vascular morphology of HCC in arterial phase and indicates the risk of MVI, Ki-67 expression and recurrence, which provides a feasible imaging technique for clinician to judge the risk of MVI pre-operation and adopt appropriate treatment. Key Points: H-CEUS can clearly show different vascular morphology of HCC in arterial phase. Vascular morphology on H-CEUS is associated with MVI status, Ki-67 expression and HCC recurrence. Preoperative MVI and Ki-67 expression prediction could help surgeons choose a more appropriate treatment plan. Graphical

Ultrasound is the most used interdisciplinary non-ionizing imaging technique in clinical pathologies of the testis. The testis may be affected by a plethora of different disorders such as vasculopathies, trauma, infections and manifestations of primary and secondary malignant masses. Conventional ultrasound represents the basic imaging modality of choice to assess scrotal disorders. Contrast-enhanced ultrasound (CEUS) can provide further information to distinguish between benign and malignant testicular mass lesions. The recent introduction of Super Resolution CEUS Micro-Vascular Imaging (MVI SR) and Time of Arrival (TOA SR) parametric mapping compliments the information provided by conventional CEUS, since these two new post-processing techniques improve the visualization of microvascular structures with slow blood flow and provide high-resolution images of the peak contrast enhancement and temporal perfusion patterns. This paper gives a comprehensive overview of differential diagnoses of the testicular disorder and their corresponding sono-morphologic correlates based on representative cases of the Interdisciplinary Ultrasound Center of the University Hospital Munich.

Ultrasound is the most used interdisciplinary imaging technique in clinical routine for assessment of renal pathologies. This includes the monitoring of cystic renal lesions, which can be classified as non-complicated or complicated and by means of occurrence as solitary or multifocal lesions. The Bosniak-classification (I–IV) classifies renal cysts in 5 different categories and is used for decisions of further clinical treatment. This classification was developed for computed tomography and has been adopted for magnetic resonance imaging as well as contrast-enhanced ultrasound. In the following review article, cystic kidney lesions and their differentiation using contrast-enhanced ultrasound are presented and an overview of the therapy options is given. In interventional procedures, CEUS can make a valuable contribution in histological sampling, reduce radiation exposure and, under certain circumstances, the number of interventions for the patient.

This comprehensive review examines recent advancements in the integration of multiparametric ultrasound for diagnostic imaging of the urinary bladder. It not only highlights the current state of ultrasound imaging but also projects its potential to further elevate standards of care in managing urinary bladder pathologies. Specifically, contrast-enhanced ultrasound (CEUS) and elastography show significant improvements in detecting bladder tumors and assessing bladder wall mechanics compared to traditional methods. The review also explores the future potential of ultrasound-mediated nanobubble destruction (UMND) as an investigational targeted cancer therapy, showcasing a novel approach that utilizes nanobubbles to deliver therapeutic genes into tumor cells with high precision. Emerging AI-driven innovations and novel techniques, such as microvascular ultrasonography (MVUS), are proving to be powerful tools for the non-invasive and precise management of bladder conditions, offering detailed insights into bladder structure and function. These advancements collectively underscore their transformative impact on the field of urology.