Adverse reactions after the use of SonoVue contrast agent: Characteristics and nursing care experience

Contrast-enhanced ultrasound (CEUS): applications from the kidneys to the bladder

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.

Contrast Reactions and Approaches to Staffing the Contrast Reaction Management Team

RATIONALE AND OBJECTIVES

Managing contrast reactions is critical as contrast reactions can be life-threatening and unpredictable. Institutions need an effective system to handle these events. Currently, there is no standard practice for assigning trainees, radiologists, non-radiologist physicians, or other non-physician providers for management of contrast reaction.

MATERIALS AND METHODS

The Association of Academic Radiologists (AAR) created a task force to address this gap. The AAR task force reviewed existing practices, studied available literature, and consulted experts related to contrast reaction management. The Society of Chairs of Academic Radiology Departments (SCARD) members were surveyed using a questionnaire focused on staffing strategies for contrast reaction management.

RESULTS

The task force found disparities in contrast reactions management across institutions and healthcare providers. There is a lack of standardized protocols for assigning personnel for contrast reaction management.

CONCLUSION

The AAR task force suggests developing standardized protocols for contrast reaction management. The protocols should outline clear roles for different healthcare providers involved in these events.

Contrast-enhanced ultrasound (CEUS) as a follow-up method after the focal treatment of renal tumors: systematic review and meta-analysis

CONTEXT

Contrast-enhanced ultrasound (CEUS) is a cost-effective radiation-free diagnostic method that can be used for renal tumor postoperative visualization after ablative treatment.

OBJECTIVE

To assess CEUS diagnostic accuracy comparing with CT and MRI as a follow-up method in short-term and long-term postoperative periods after renal tumor ablation.

MATERIALS AND METHODS

A systematic review and meta-analysis were performed in Scopus and Medline databases using the query "(kidney OR rena* OR RCC) AND (ablation OR RFA OR MWA OR cryo*) AND CEUS". The endpoint of the study was the evaluation of the overall accuracy of CEUS.

RESULTS

Twelve trials were included in the review. With CT or MRI as a reference, for a short-term group (< 6 weeks after ablation) pooled sensitivity was 90.2%, I2 = 0%; pooled specificity was 99.3%, I2 = 0%; pooled NPV was 98.6%, I2 = 0%; pooled PPV was 94.6%, I2 = 0%; the AUC on the SROC curve was 0.971. For the long-term group (> 6 weeks after ablation), pooled sensitivity was 95.3%, I2 = 0%; pooled specificity was 97.6%, I2 = 0%; PPV was 74.2%, I2 = 4%; NPV was 99.4%, I2 = 5%; AUC = 0.93.

CONCLUSION

CEUS has high sensitivity and specificity in ruling out the presence of local recurrence after renal tumor ablation with a higher risk of false-positive results within follow-up > 6 weeks compared with that for CT or MRI. Further studies with a unified protocol and morphological control of local renal tumor recurrence after ablation are needed.

The Utility of Contrast-Enhanced Ultrasound (CEUS) in Assessing the Risk of Malignancy in Thyroid Nodules

BACKGROUND

Ultrasonography is a primary method used in the evaluation of thyroid nodules, but no single feature of this method predicts malignancy with high accuracy. Therefore, this paper aims to assess the utility of contrast-enhanced ultrasound (CEUS) in the differential diagnosis of thyroid nodules.

METHODS

The study group comprised 188 adult patients (155 women and 33 men) who preoperatively underwent CEUS of a thyroid nodule classified as Bethesda categories II-VI after fine-needle aspiration biopsy. During the CEUS examination, 1.5 mL of SonoVue contrast was injected intravenously, after which 15 qualitative CEUS enhancement patterns were analysed.

RESULTS

The histopathologic results comprised 65 benign thyroid nodules and 123 thyroid carcinomas. The dominant malignant CEUS features, such as hypo- and heterogeneous enhancement and slow wash-in phase, were evaluated, whereas high enhancement, ring enhancement, and a slow wash-out phase were assessed as predictors of benign lesions. Two significant combinations of B-mode and CEUS patterns were noted, namely, hypoechogenicity with heterogeneous enhancement and non-smooth margins with hypo- or iso-enhancement.

CONCLUSIONS

The preliminary results indicate that CEUS is a useful tool in assessing the risk of malignancy of thyroid lesions. The combination of the qualitative enhancement parameters and B-mode sonographic features significantly increases the method's usefulness.

Intravenous administration of ultrasound contrast to critically ill pediatric patients

BACKGROUND

The off-label use of contrast-enhanced ultrasound has been increasingly used for pediatric patients.

OBJECTIVE

The purpose of this retrospective study is to report any observed clinical changes associated with the intravenous (IV) administration of ultrasound contrast to critically ill neonates, infants, children, and adolescents.

MATERIALS AND METHODS

All critically ill patients who had 1 or more contrast-enhanced ultrasound scans while being closely monitored in the neonatal, pediatric, or pediatric cardiac intensive care units were identified. Subjective and objective data concerning cardiopulmonary, neurological, and hemodynamic monitoring were extracted from the patient's electronic medical records. Vital signs and laboratory values before, during, and after administration of ultrasound contrast were obtained. Statistical analyses were performed using JMP Pro, version 15. Results were accepted as statistically significant for P-value<0.05.

RESULTS

Forty-seven contrast-enhanced ultrasound scans were performed on 38 critically ill patients, 2 days to 17 years old, 19 of which were female (50%), and 19 had history of prematurity (50%). At the time of the contrast-enhanced ultrasound scans, 15 patients had cardiac shunts or a patent ductus arteriosus, 25 had respiratory failure requiring invasive mechanical oxygenation and ventilation, 19 were hemodynamically unstable requiring continual vasoactive infusions, and 8 were receiving inhaled nitric oxide. In all cases, no significant respiratory, neurologic, cardiac, perfusion, or vital sign changes associated with IV ultrasound contrast were identified.

CONCLUSION

This study did not retrospectively identify any adverse clinical effects associated with the IV administration of ultrasound contrast to critically ill neonates, infants, children, and adolescents.

Effectiveness of contrast-enhanced duplex ultrasound for detecting renal artery stenosis: A systematic review

PURPOSE

Contrast-enhanced duplex ultrasound (CEUS) might be a useful tool to diagnosing renal artery stenosis (RAS). We amalgamated and reviewed the evidence assessing the diagnostic accuracy of CEUS on detecting RAS compared to angiography.

METHODS

This preregistered systematic review included studies that compared the presence of RAS via CEUS with angiography. Sources were searched in November 2022 and included Scopus, EMBASE, MEDLINE, CINAHL, and Academic Search Premier (n = 1717). The Quality Assessment of Diagnostic Studies 2 tool assessed study quality. Results are presented narratively.

RESULTS

The studies included (n = 11) had a total of 447 unique participants (193 females) and average age of 56 ± 9 years. Five of eleven studies investigated CEUS using SonoVue contrast agent and reported an average accuracy (91% ± 2%), sensitivity (91% ± 3%), specificity (90% ± 5%), negative predictive value (86% ± 6%), and positive predictive value (94% ± 1%) with all values >80%. The accuracy of CEUS using other types of contrast agent (n = 6), including Levovsit (n = 3/6), Definity (n = 1/6), perfienapent emulsion (n = 1/6), and perfluorocarbon-exposed sonicated dextrose albumin (n = 1/6) was mixed. These studies detected an average accuracy of 91 ± 11% (n = 2/3% > 80%), sensitivity of 98% ± 4%, (n = 3/3% > 80%), and specificity of 86% ± 10% (n = 2/3% > 80%). Included studies had generally low risk of bias and applicability concerns except for unclear flow and timing (n = 7/11) and applicability of patient selection (n = 4/11).

CONCLUSION

Despite being limited by the heterogeneity of included studies, our review indicates a high overall diagnostic accuracy for CEUS to detect RAS compared to angiography, with the largest evidence-base for SonoVue contrast. Radiologists and hospital decision makers should consider CEUS as an acceptable alternative to angiography.

The Performance of Different Parametric Ultrasounds in Prostate Cancer Diagnosis: Correlation with Radical Prostatectomy Specimens

BACKGROUND

Prostate cancer is a prevalent cancer among men. Multiparametric ultrasound [mpUS] is a diagnostic instrument that uses various types of ultrasounds to diagnose it. This systematic review aims to evaluate the performance of different parametric ultrasounds in diagnosing prostate cancer by associating with radical prostatectomy specimens.

METHODOLOGY

A review was performed on various ultrasound parameters using five databases. Systematic review tools were utilized to eliminate duplicates and identify relevant results. Reviewers used the Quality Assessment of Diagnostic Accuracy Results [QUADAS-2] to evaluate the bias and applicability of the study outcomes.

RESULT

Between 2012 and 2023, eleven studies were conducted to evaluate the performance of the different ultrasound parametric procedures in detecting prostate cancer using grayscale TRUS, SWE, CEUS, and mpUS. The high sensitivity of these procedures was found at 55%, 88.6%, 81%, and 74%, respectively. The specificity of these procedures was found to be 93.4%, 97%, 88%, and 59%, respectively. This high sensitivity and specificity may be associated with the large lesion size. The studies revealed that the sensitivity of these procedures in diagnosing clinically significant prostate cancer was 55%, 73%, 70%, and 74%, respectively, while the specificity was 61%, 78.2%, 62%, and 59%, respectively.

CONCLUSIONS

The mpUS procedure provides high sensitivity and specificity in PCa detection, especially for clinically significant prostate cancer.

Diagnostic efficacy of contrast-enhanced gastric ultrasonography in staging gastric cancer: a meta-analysis

BACKGROUND

As comprehensive surgical management for gastric cancer becomes increasingly specialized and standardized, the precise differentiation between ≤T1 and ≥T2 gastric cancer before endoscopic intervention holds paramount clinical significance.

OBJECTIVE

To evaluate the diagnostic efficacy of contrast-enhanced gastric ultrasonography in differentiating ≤T1 and ≥T2 gastric cancer.

METHODS

PubMed, Web of Science, and Medline were searched to collect studies published from January 1, 2000 to March 16, 2023 on the efficacy of either double contrast-enhanced gastric ultrasonography (D-CEGUS) or oral contrast-enhanced gastric ultrasonography (O-CEGUS) in determining T-stage in gastric cancer. The articles were selected according to specified inclusion and exclusion criteria, and the quality of the included literature was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 scale. Meta-analysis was performed using Stata 12 software with data from the 2 × 2 crosslinked tables in the included literature.

RESULTS

In total, 11 papers with 1124 patients were included in the O-CEGUS analysis, which revealed a combined sensitivity of 0.822 (95% confidence interval [CI] = 0.753-0.875), combined specificity of 0.964 (95% CI = 0.925-0.983), and area under the summary receiver operating characteristic (sROC) curve (AUC) of 0.92 (95% CI = 0.89-0.94). In addition, five studies involving 536 patients were included in the D-CEGUS analysis, which gave a combined sensitivity of 0.733 (95% CI = 0.550-0.860), combined specificity of 0.982 (95% CI = 0.936-0.995), and AUC of 0.93 (95% CI = 0.91-0.95). According to the I2 and P values ​​of the forest plot, there was obvious heterogeneity in the combined specificities of the included papers. Therefore, the two studies with the lowest specificities were excluded from the O-CEGUS and D-CEGUS analyses, which eliminated the heterogeneity among the remaining literature. Consequently, the combined sensitivity and specificity of the remaining studies were 0.794 (95% CI = 0.710-0.859) and 0.976 (95% CI = 0.962-0.985), respectively, for the O-CEDUS studies and 0.765 (95% CI = 0.543-0.899) and 0.986 (95% CI = 0.967-0.994), respectively, for the D-CEGUS studies. The AUCs were 0.98 and 0.99 for O-CEGUS and D-CEGUS studies, respectively.

CONCLUSION

Both O-CEGUS and D-CEGUS can differentiate ≤T1 gastric cancer from ≥T2 gastric cancer, thus assisting the formulation of clinical treatment strategies for patients with very early gastric cancer. Given its simplicity and cost-effectiveness, O-CEGUS is often favored as a staging method for gastric cancer prior to endoscopic intervention.

3-D Contrast-Enhanced Fusion Ultrasound for Accurate Volume Assessment of Vessel Lumen and Plaque in Carotid Artery Disease as Compared With Computed Tomography Angiography

OBJECTIVE

Three-dimensional contrast-enhanced fusion ultrasound (CEFUS) of atherosclerotic carotid arteries provides spatial visualization of the vessel lumen, creating a lumenography. As in 3-D computed tomography angiography (CTA), 3-D CEFUS outlines the contrast-filled lumen. Plaque and vessel contours are distinguished in 3-D CEFUS, allowing plaque volume quantification as a valid estimate of carotid plaque burden. Three-dimensional CEFUS is unproven in intermodality studies, vindicating the assessment of 3-D CEFUS applicability and comparing 3-D CEFUS and 3-D CTA lumenography as a proof-of-concept study.

METHODS

Using an ultrasound system with magnetic tracking, a linear array transducer and SonoVue contrast agent, 3-D CEFUS acquisitions were generated by spatial stitching of serial 2-D images. From 3-D CEFUS and 3-D CTA imaging, the atherosclerotic carotid arteries were reconstructed with lumenography in an offline software program for lumen and plaque volume quantification. Bland-Altman analysis was used for inter-image modality agreement.

RESULTS

The study included 39 carotid arteries. Mean lumen and plaque volume in 3-D CEFUS were 0.63 cm3 (standard deviation [SD]: 0.26) and 0.62 cm3 (SD: 0.26), respectively. Lumen volume differences between 3-D CEFUS and 3-D CTA were non-significant, with a mean difference of 0.01 cm3 (SD: 0.02, p = 0.26) and limits of agreement (LoA) range of ±0.11 cm3. Mean plaque volume difference was -0.12 cm3 (SD: 0.19, p = 0.006) with a LoA range of ±0.39 cm3.

CONCLUSION

There was strong agreement in lumenography between 3-D CEFUS and 3-D CTA. The interimage modality difference in plaque volumes was substantial because of challenging vessel wall definition in 3-D CTA. Three-dimensional CEFUS is viable in quantifying carotid plaque volume burden and can potentially monitor plaque development over time.

Thyroid ultrasound and its ancillary techniques

Ultrasound (US) of the thyroid has been used as a diagnostic tool since the late 1960s. US is the most important imaging tool for diagnosing thyroid disease. In the majority of cases a correct diagnosis can already be made in synopsis of the sonographic together with clinical findings and basal thyroid hormone parameters. However, the characterization of thyroid nodules by US remains challenging. The introduction of Thyroid Imaging Reporting and Data Systems (TIRADSs) has improved diagnostic accuracy of thyroid cancer significantly. Newer techniques such as elastography, superb microvascular imaging (SMI), contrast enhanced ultrasound (CEUS) and multiparametric ultrasound (MPUS) expand diagnostic options and tools further. In addition, the use of artificial intelligence (AI) is a promising tool to improve and simplify diagnostics of thyroid nodules and there is evidence that AI can exceed the performance of humans. Combining different US techniques with the introduction of new software, the use of AI, FNB as well as molecular markers might pave the way for a completely new area of diagnostic accuracy in thyroid disease. Finally, interventional ultrasound using US-guided thermal ablation (TA) procedures are increasingly proposed as therapy options for benign as well as malignant thyroid diseases.

Non-contrast ultrasound image analysis for spatial and temporal distribution of blood flow after spinal cord injury

Ultrasound technology can provide high-resolution imaging of blood flow following spinal cord injury (SCI). Blood flow imaging may improve critical care management of SCI, yet its duration is limited clinically by the amount of contrast agent injection required for high-resolution, continuous monitoring. In this study, we aim to establish non-contrast ultrasound as a clinically translatable imaging technique for spinal cord blood flow via comparison to contrast-based methods and by measuring the spatial distribution of blood flow after SCI. A rodent model of contusion SCI at the T12 spinal level was carried out using three different impact forces. We compared images of spinal cord blood flow taken using both non-contrast and contrast-enhanced ultrasound. Subsequently, we processed the images as a function of distance from injury, yielding the distribution of blood flow through space after SCI, and found the following. (1) Both non-contrast and contrast-enhanced imaging methods resulted in similar blood flow distributions (Spearman's ρ = 0.55, p < 0.0001). (2) We found an area of decreased flow at the injury epicenter, or umbra (p < 0.0001). Unexpectedly, we found increased flow at the periphery, or penumbra (rostral, p < 0.05; caudal, p < 0.01), following SCI. However, distal flow remained unchanged, in what is presumably unaffected tissue. (3) Finally, tracking blood flow in the injury zones over time revealed interesting dynamic changes. After an initial decrease, blood flow in the penumbra increased during the first 10 min after injury, while blood flow in the umbra and distal tissue remained constant over time. These results demonstrate the viability of non-contrast ultrasound as a clinical monitoring tool. Furthermore, our surprising observations of increased flow in the injury periphery pose interesting new questions about how the spinal cord vasculature reacts to SCI, with potentially increased significance of the penumbra.

Assessment of renal quality with quantitative contrast-enhanced ultrasound (CEUS) for differentiating kidney histopathology before procurement

Purpose: This study aimed to investigate the use of contrast-enhanced ultrasonography (CEUS) to assess the kidneys' quality before procurement. Methods: This prospective study included 74 donors and 148 recipients of kidneys. 119 kidneys underwent quantitative analysis. Before organ procurement, potential kidney donors underwent CEUS, though organ procurement involved a zero-point puncture biopsy. CEUS parameters of the renal cortex and medulla were evaluated, including rise time (RT), time to peak (TTP), the area under the curve (AUC), wash-in slope (WIS), peak intensity (PI), and mean transit time (MTT). Donors' kidneys were classified based on their pathological. Additionally, short-term clinical indicators of renal recipients were collected and analyzed to determine whether the patients had delayed recovery of renal allograft function. Results: This experiment included 148 cases of kidney information, divided into two groups based on the Remuzzi score of the kidneys. However, 29 kidneys were excluded from the quantitative analysis due to loss or low quality of CEUS images. Comparing the time-intensity curve (TIC) of renal cortical region of interest (ROI), we found that the group with lower pathological scores exhibited higher PI (P=0.002), AUC(P=0.003), and WIS (P=0.009). TIC comparison results for renal medulla ROI revealed that the group with lower pathological scores had higher PI (P=0.010), AUC (P=0.023), and WIS (P=0.024). Conclusions: This study highlighted the potential of CEUS as a non-invasive, safe, and real-time examination method that correlates with the Remuzzi score and renal pathology. Therefore, it can be used as a prospective preoperative non-invasive evaluation method for the donor's kidney.

Contrast echocardiography: a practical guideline from the British Society of Echocardiography

Ultrasound contrast agents (UCAs) have a well-established role in clinical cardiology. Contrast echocardiography has evolved into a routine technique through the establishment of contrast protocols, an excellent safety profile, and clinical guidelines which highlight the incremental prognostic utility of contrast enhanced echocardiography. This document aims to provide practical guidance on the safe and effective use of contrast; reviews the role of individual staff groups; and training requirements to facilitate its routine use in the echocardiography laboratory.

Contrast-Enhanced Ultrasound Feasibility in Assessing Carotid Plaque Vulnerability-Narrative Review

The risk assessment for carotid atherosclerotic lesions involves not only determining the degree of stenosis but also plaque morphology and its composition. Recently, carotid contrast-enhanced ultrasound (CEUS) has gained importance for evaluating vulnerable plaques. This review explores CEUS's utility in detecting carotid plaque surface irregularities and ulcerations as well as intraplaque neovascularization and its alignment with histology. Initial indications suggest that CEUS might have the potential to anticipate cerebrovascular incidents. Nevertheless, there is a need for extensive, multicenter prospective studies that explore the relationships between CEUS observations and patient clinical outcomes in cases of carotid atherosclerotic disease.

Comparative analysis of ultrasonic elastosonography and contrast-enhanced ultrasonography in the diagnosis of benign and malignant intraocular tumors

PURPOSE

To compare the diagnostic value of ultrasonic elastosonography (UE) and contrast-enhanced ultrasonography (CEUS) for benign and malignant intraocular tumors.

METHODS

This retrospective study enrolled patients with intraocular tumors at Beijing Tongren Hospital, Capital Medical University (August 2016 to January 2020). The strain rate ratio (strain rate of tumor tissue divided by strain rate of surrounding normal tissue) was measured by UE. CEUS was performed using SonoVue® contrast agent. The performance of each method at differentiating benign from malignant intraocular tumors was evaluated by receiver operating characteristic curve analysis.

RESULTS

The analysis included 147 eyes in 145 patients (45.6 ± 13.4 years-old; 66 males): 117 patients (119 eyes) with malignant tumors and 28 patients (28 eyes) with benign tumors. At an optimal cutoff of 22.67 for the strain rate ratio, UE distinguished benign from malignant tumors with a sensitivity of 86.6% and a specificity of 96.4%. CEUS showed that 117 eyes with malignant tumors had a fast-in, fast-out time-intensity curve, and only two eyes with malignant tumors had a fast-in, slow-out curve, while all 28 eyes with benign tumors had a fast-in, slow-out curve. CEUS differentiated benign from malignant tumors with a sensitivity of 98.3% and a specificity of 100%. The diagnostic results differed significantly between the two methods (P = 0.004, McNemar test). The diagnostic performances of the two tests were moderately consistent (κ = 0.657, P < 0.001).

CONCLUSION

Both CEUS and UE have good diagnostic value in the differentiation of benign intraocular tumors from malignant intraocular tumors.

The Use of Contrast-Enhanced Ultrasound (CEUS) in the Evaluation of the Neonatal Brain

In recent years, advancements in technology have allowed the use of contrast-enhanced ultrasounds (CEUS) with high-frequency transducers, which in turn, led to new possibilities in diagnosing a variety of diseases and conditions in the field of radiology, including neonatal brain imaging. CEUSs overcome some of the limitations of conventional ultrasounds (US) and Doppler USs. It allows the visualization of dynamic perfusion even in the smallest vessels in the whole brain and allows the quantitative analysis of perfusion parameters. An increasing number of articles are published on the topic of the use of CEUSs on children each year. In the area of brain imaging, the CEUS has already proven to be useful in cases with clinical indications, such as hypoxic-ischemic injuries, stroke, intracranial hemorrhages, vascular anomalies, brain tumors, and infections. We present and discuss the basic principles of the CEUS and its safety considerations, the examination protocol for imaging the neonatal brain, and current and emerging clinical applications.

Risk Factors of Contrast Agent Intravasation With Sulfur Hexafluoride Microbubble During Hysterosalpingo-Contrast Sonography

OBJECTIVES

To analyze the risk factors of sulfur hexafluoride microbubble contrast agent intravasation during hysterosalpingo-contrast sonography (HyCoSy), and to explore a simple prediction model by the obvious clinical history.

METHODS

This was a retrospective study included 299 infertility women who had undergone HyCoSy examination from July 1, 2018 to June 31, 2019. The factors were recorded, including age, endometrial thickness, balloon length, infertility type, history of intrauterine surgery, history of pelvic surgery, and tubal patency. The method of multivariate logistic regression analysis was adopted to analyze the risk factors affecting the contrast agent intravasation, and the receiver operating characteristic curves were plotted to test their efficacy.

RESULTS

Secondary infertility, a history of intrauterine surgery, thin endometrial thickness, and tubal obstruction were all risk factors of the occurrence of intravasation (P < .05). And the area under the receiver operating characteristic curves of the multifactor-combined prediction model of the intravasation was significantly larger than that of single-factor.

CONCLUSIONS

Sonographers and gynecologists should be familiar with the risk factors of intravasation and select the appropriate timing of HyCoSy toward reducing the occurrence of intravasation and other complications after thoroughly explaining and communicating with the patients.

Safety Analysis of Adverse Events of Ultrasound Contrast Agent Lumason/SonoVue in 49,100 Patients

This study assessed the incidence of mild, moderate and severe adverse events (AEs) and examined their association with age, sex, body region examined, time to event and duration of the AE(s) in a large cohort of patients who underwent contrast-enhanced ultrasound (CEUS) with Lumason/SonoVue. In this retrospective observational study, 49,100 patients who underwent CEUS were analyzed. Forty-three (0.088%) patients experienced AEs, with 23 (0.047%) patients experiencing mild AEs, 13 (0.026%) experiencing moderate AEs and 7 (0.014%) experiencing severe AEs. No fatal event occurred. There was no age- or sex-related difference in the incidence of the AE(s) (p = 0.158 and p = 0.474). Inpatients (0.17%) more often experienced AEs than outpatients (0.06%, p = 0.003). The mean time to event for mild and moderate AEs was 14.50 ± 6.96 and 15.75 ± 10.40 min, respectively, whereas that for severe AEs was 1.89 ± 1.21 min after the injection. The remission time for mild and moderate AEs was approximately 30-40 min, and all patients with severe AEs recovered within 12 h. Twenty-one (48.8%) patients received medical treatment. In summary, Lumason/SonoVue has a good safety profile with a low incidence of AEs, most of which are mild with a short time to event and duration.

Operator's Influence on Contrast Agent Intravasation During Hysterosalpingo-Contrast Sonography: Explanation Based on a Physics Model

Objective

To analyze the risk factors of the operators on contrast agent intravasation during hysterosalpingo-contrast sonography (HyCoSy).

Methods

We retrospectively collected 399 infertile women who underwent HyCoSy by the same sonographer. These patients were divided into two groups according to the way how the assistants connected the syringe to the uterus radiography catheter to inject the contrast agent. We analyzed whether the use of different contrast bolus injection methods had any influence on the incidence of intravasation during HyCoSy.

Results

There was no significant difference between the two groups with different cross-sectional areas of the syringe outflow tract in the risk variables for intravasation, but the intravasation rates of the two groups were different, 26.4% in group A and 17.1% in group B, P <0.05. The primary manifestation was that when both fallopian tubes were unobstructed, the intravasation rate of group B with smaller cross-sectional area of the outflow tract of the syringe was lower, and the difference was statistically significant. The inferences drawn from our physics model were also in line with the clinical results.

Conclusion

The influence of different operators on the contrast agent intravasation rate of HyCoSy cannot be ignored. The assistants of HyCoSy examination should inject the contrast agent slowly and steady, and a needle can be used as a flow restrictor to control the flow into the uterine cavity per unit time, slow down the rising speed of intrauterine pressure, and avoid the accumulation of contrast agent in the uterine cavity, so as to reduce the intravasation caused by operator factors.

Point-of-care contrast enhanced lung ultrasound and COVID-19

OBJECTIVES

Bedside lung ultrasound has been indispensable during the coronavirus disease 2019 (COVID-19) pandemic, allowing us to rapidly assess critically unwell patients. We demonstrate the unique application of contrast-enhanced ultrasound with the aim of further understanding this disease.

METHODS

Patient demographics were recorded alongside recent cross-sectional imaging and inflammatory markers. Ultrasound was conducted by experienced operators in a portable setting. Conventional six-point lung ultrasound method was used to evaluate B-lines, small (subpleural) consolidation and the pleura. Areas of small consolidation were targeted after intravenous administration of ultrasound contrast.

RESULTS

The areas of small consolidations, a potential sign of pneumonia on B-mode lung ultrasound, usually enhance on contrast-enhanced ultrasound. Our study revealed these areas to be avascular, indicating an underlying thrombotic/infarction process. Findings were present in 100% of the patients we examined. We have also shown that the degree of infarction correlates with CT severity (r = 0.4) and inflammatory markers, and that these areas improve as patients recover.

CONCLUSIONS

We confirmed the theory of immune thrombus by identifying the presence of microthrombi in the lungs of 100% of our patients, despite 79% having had a recent negative CT pulmonary angiogram study. contrast-enhanced ultrasound can be utilised to add confidence to an uncertain COVID-19 diagnosis and for prognosticating and monitoring progress in confirmed COVID-19 patients. Contrast-enhanced ultrasound is clearly very different to CT, the gold standard, and while there are specific pathologies that can only be detected on CT, contrast-enhanced ultrasound has many advantages, most notability the ability to pick up microthrombi at the periphery of the lungs.

Intravenous contrast medium extravasation: systematic review and updated ESUR Contrast Media Safety Committee Guidelines

NEED FOR A REVIEW

Guidelines for management and prevention of contrast media extravasation have not been updated recently. In view of emerging research and changing working practices, this review aims to inform update on the current guidelines.

AREAS COVERED

In this paper, we review the literature pertaining to the pathophysiology, diagnosis, risk factors and treatments of contrast media extravasation. A suggested protocol and guidelines are recommended based upon the available literature.

KEY POINTS

• Risk of extravasation is dependent on scanning technique and patient risk factors. • Diagnosis is mostly clinical, and outcomes are mostly favourable. • Referral to surgery should be based on clinical severity rather than extravasated volume.

Contrast-Enhanced Ultrasound for Evaluation of Pleural Effusion: A Pictorial Essay

B-mode ultrasound (B-US) is the standard imaging modality to evaluate pleural effusion. The value of B-US for assessing the malignancy of a pleural effusion (PE) is limited. For this purpose, computed tomography (CT) and thoracoscopy are the methods of choice to evaluate an effusion. The aim of this Pictorial Essay is to demonstrate contrast-enhanced ultrasound (CEUS) as a method in addition to B-US and CT for the evaluation of PE taking into account the clinical background. The characteristic patterns of pleural pathologies, effusion morphology, and associated lung parenchymal consolidations are presented.

Detection of Carotid Atherosclerotic Intraplaque Neovascularization Using Superb Microvascular Imaging: A Meta-Analysis

OBJECTIVES

Although superb microvascular imaging (SMI) (Toshiba/Canon, Tokyo, Japan) has enabled routine characterization of intraplaque neovascularization (IPN) features in patients with carotid stenosis, no reports have been published on the multicenter and large sample size research in this aspect. The efficacy of SMI in detecting carotid IPN has not been concluded. This study aimed to assess the efficacy of SMI comparing with contrast-enhanced carotid ultrasonography (CEUS) in the detection of carotid IPN or pathologic evaluations of IPN correlated with a history of stroke or transient ischemic attack (TIA).

METHODS

Web of Science, Cochrane Library, PubMed, Embase, and Scopus were searched up to August 2020 to identify peer-reviewed human studies on the diagnostic accuracy of SMI in detecting IPN. For the selected study, the correlation coefficient R and Kappa index between SMI and CEUS in detecting IPN were calculated. The correlation coefficient R between SMI in identifying IPN and pathologic evaluations of IPN and the odds ratio of IPN detected by SMI and history of stroke or TIA were also extracted. The subgroup analysis was performed to indicate the source of heterogeneity.

RESULTS

Our search identified 11 reports enrolling a total of 605 carotid stenosis patients. Carotid IPN detected by SMI was significantly correlated with which detected by CEUS (R, 0.89; 95% CI, 0.80-0.94; P = .00, and Kappa index, 0.73; 95% CI, 0.67-0.80; P = .00). Notably, a significant correlation was observed in SMI in detecting IPN and pathologic evaluations of IPN (R, 0.52; 95% CI, 0.40-0.62; P = .00). The odds ratio of IPN detected by SMI and history of stroke or TIA was pooled summary with statistical significance (OR, 3.33; 95% CI, 1.78-6.23; P = .00). In subgroup analysis, lower heterogeneity was associated with the degree of carotid stenosis, patients from which country, and types of equipment.

CONCLUSIONS

SMI and CEUS display an excellent agreement in detecting carotid IPN. IPN detected by SMI shows high consistency with pathologic evaluations of IPN. Individuals with carotid IPN are more likely to develop stroke or TIA than those without carotid IPN.

Transcutaneous B-mode ultrasound (TUS) and contrast-enhanced ultrasound (CEUS) pattern of mediastinal tumors: a pictorial essay

Sound reflection from bony structures and from air-filled lung parenchyma limits transcutaneous B-mode thoracic ultrasound of the mediastinum. Computed tomography and magnetic resonance imaging of the thorax are the primary overview imaging modalities for mediastinal pathologies. However, pathological processes originating from the mediastinum can be sonographically visualized and evaluated in the presence of displacing or infiltrative growth. The aim of this pictorial essay is to demonstrate contrast-enhanced ultrasound as a method complementing B-mode ultrasound, computed tomography, and magnetic resonance imaging for the evaluation of mediastinal tumors, taking into account the clinical background. The characteristic perfusion patterns of mediastinal pathology are presented.

Perfusion Patterns of Peripheral Pulmonary Lesions in COVID-19 Patients Using Contrast-Enhanced Ultrasound (CEUS): A Case Series

PURPOSE

To describe perfusion patterns of peripheral pulmonary lesions (PPLs) in COVID-19 patients using contrast-enhanced ultrasound (CEUS).

PATIENTS AND METHODS

From April 2020 until July 2020, 11 consecutive patients with RT-PCR-confirmed COVID-19 and PPLs sized over 5 mm were investigated by B-mode ultrasound (B-US) and CEUS. The homogeneity of enhancement (homogeneous and inhomogeneous) was examined retrospectively using CEUS. An inhomogeneous enhancement was defined as a perfused lesion with coexisting non-perfused areas (NPA).

RESULTS

On B-US, all 11 patients showed an interstitial syndrome (B-lines) with PPLs between 0.5 and 6 cm. On CEUS, all cases showed peripheral NPA during the complete CEUS examination. One patient underwent a partial lung resection with subsequent histopathological examination. The histological examination showed vasculitis, microthrombus in the alveolar capillary, and small obliterated vessels.

CONCLUSION

In our case series, PPLs in patients with RT-PCR-confirmed COVID-19 infection presented a CEUS pattern with NPA during the complete CEUS examination. Our findings suggest a peripheral pulmonary perfusion disturbance in patients with COVID-19 infection. In 1 case, the histopathological correlation with the perfusion disturbance in the PPL was proven.

Contrast-enhanced ultrasound: a comprehensive review of safety in children

Contrast-enhanced ultrasound (CEUS) has been increasingly used in pediatric radiology practice worldwide. For nearly two decades, CEUS applications have been performed with the off-label use of gas-containing second-generation ultrasound contrast agents (UCAs). Since 2016, the United States Food and Drug Administration (FDA) has approved the UCA Lumason for three pediatric indications: the evaluation of focal liver lesions and echocardiography via intravenous administration and the assessment of vesicoureteral reflux via intravesical application (contrast-enhanced voiding urosonography, ceVUS). Prior to the FDA approval of Lumason, numerous studies with the use of second-generation UCAs had been conducted in adults and children. Comprehensive protocols for clinical safety evaluations have demonstrated the highly favorable safety profile of UCA for intravenous, intravesical and other intracavitary uses. The safety data on CEUS continue to accumulate as this imaging modality is increasingly utilized in clinical settings worldwide. As of August 2021, 57 pediatric-only original research studies encompassing a total of 4,518 children with 4,906 intravenous CEUS examinations had been published. As in adults, there were a few adverse events; the majority of these were non-serious, although very rarely serious anaphylactic reactions were reported. In the published pediatric-only intravenous CEUS studies included in our analysis, the overall incidence rate of serious adverse events was 0.22% (10/4,518) of children and 0.20% (10/4,906) of all CEUS examinations. Non-serious adverse events from the intravenous CEUS were observed in 1.20% (54/4,518) of children and 1.10% (54/4,906) of CEUS examinations. During the same time period, 31 studies with the intravesical use of UCA were conducted in 12,362 children. A few non-serious adverse events were encountered (0.31%; 38/12,362), but these were most likely attributable to the bladder catheterization rather than the UCA. Other developing clinical applications of UCA in children, including intracavitary and intralymphatic, are ongoing. To date, no serious adverse events have been reported with these applications. This article reviews the existing pediatric CEUS literature and provides an overview of safety-related information reported from UCA uses in children.

Performance of Contrast-Enhanced Ultrasound in Thyroid Nodules: Review of Current State and Future Perspectives

Ultrasound has been established as a baseline imaging technique for thyroid nodules. The main advantage of adding CEUS is the ability to assess the sequence and intensity of vascular perfusion and hemodynamics in the thyroid nodule, thus providing real-time characterization of nodule features, considered a valuable new approach in the determination of benign vs. malignant nodules. Original studies, reviews and six meta-analyses were included in this article. A total of 624 studies were retrieved, and 107 were included in the study. As recognized for thyroid nodule malignancy risk stratification by US, for acceptable accuracy in malignancy a combination of several CEUS parameters should be applied: hypo-enhancement, heterogeneous, peripheral irregular enhancement in combination with internal enhancement patterns, and slow wash-in and wash-out curve lower than in normal thyroid tissue. In contrast, homogeneous, intense enhancement with smooth rim enhancement and "fast-in and slow-out" are indicative of the benignity of the thyroid nodule. Even though overlapping features require standardization, with further research, CEUS may achieve reliable performance in detecting or excluding thyroid cancer. It can also play an operative role in guiding ablation procedures of benign and malignant thyroid nodules and metastatic lymph nodes, and providing accurate follow-up imaging to assess treatment efficacy.

Ultrasound microvasculature imaging with entropy-based radiality super-resolution (ERSR)

Objective:Microvasculature is highly relevant to the occurrence and development of pathologies such as cancer and diabetes. Ultrasound localization microscopy (ULM) has bypassed the diffraction limit and demonstrated its great potential to provide new imaging modality and establish new diagnostic criteria in clinical application. However, sparse microbubble distribution can be a significant bottleneck for improving temporal resolution, even for further clinical translation. Other important challenges for ULM to tackle in clinic also include high microbubble concentration and low frame rate.Approach:As part of the efforts to facilitate clinical translation, this paper focused on the low frame rate and the high microbubble distribution issue and proposed a new super-resolution imaging strategy called entropy-based radiality super-resolution (ERSR). The feasibility of ERSR is validated with simulations, phantom experiment and contrast-enhanced ultrasound scan of rabbit sciatic nerve with clinical accessible ultrasound system.Main results:ERSR can achieve 10 times improvement in spatial resolution compared to conventional ultrasound imaging, higher temporal resolution (∼10 times higher) and contrast-to-noise ratio under high-density microbubbles, compared with ULM under low-density microbubbles.Significance:We conclude ERSR could be a valuable imaging tool with high spatio-temporal resolution for clinical diagnosis and assessment of diseases potentially.

Contrast-enhanced ultrasound for screening hepatocellular carcinoma: an implemented program at a semi-rural academic center

Purpose

To describe our early experience using a contrast-enhanced ultrasound (CEUS) protocol for surveillance of hepatocellular carcinoma (HCC) at a semi-rural academic medical center.

Methods

Retrospective, longitudinal study of the first 100 patients who underwent CEUS liver screening imaging over 2 years. Each patient underwent a standard of care abdominal ultrasound, which was checked with the radiologist, who searched for a focal lesion on the cine clips to target specifically with contrast. If none was present, the HCC contrast-enhanced screening protocol consisting of individual sweeps of the right and left lobes was performed from 0 to 60 s and 3–4 min post contrast—Lumason was utilized. Images, report details, and patient demographics were analyzed.

Results

66 men and 34 women (average age, 59 ± 13 years) were included. On average, the distance from patient’s home to our institution was 39 miles (range 2–179 miles). The majority of our patients were covered under Private insurance (46%) with 43% covered by Medicare. CEUS exams on average took 35 min to complete. Lumason was administered in split doses for an average total of 5 mL per exam. Of the 10 lesions identified, there were five LI-RADS 3, two LI-RADS 4, one LI-RADS 5, two LI-RADS M, and one bland portal vein thrombus. There were no complications reported.

Conclusion

This semi-rural single-center study demonstrates the feasibility of starting a HCC CEUS screening program. CEUS can be performed in conjunction with routine ultrasound imaging with added benefit of identifying and characterizing lesions in one setting.

How to Perform Intra-Operative Contrast-Enhanced Ultrasound of the Brain-A WFUMB Position Paper

Intra-operative ultrasound has become a relevant imaging modality in neurosurgical procedures. While B-mode, with its intrinsic limitations, is still considered the primary ultrasound modality, intra-operative contrast-enhanced ultrasound (ioCEUS) has more recently emerged as a powerful tool in neurosurgery. Though still not used on a large scale, ioCEUS has proven its utility in defining tumor boundaries, identifying lesion vascular supply and mapping neurovascular architecture. Here we propose a step-by-step procedure for performing ioCEUS analysis of the brain, highlighting its neurosurgical applications. Moreover, we provide practical advice on the use of ultrasound contrast agents and review technical ultrasound parameters influencing ioCEUS imaging.

Contrast-Enhanced Ultrasound in Chronic Liver Diseases

Contrast-enhanced ultrasound (CEUS) is a safe adjunct tool for liver imaging and can be an alternative to computed tomography or MR imaging. CEUS has a proven track record in guiding management for patients with chronic liver disease who need further evaluation of focal liver lesions. CEUS is a dynamic examination with high temporal and spatial resolution. CEUS uses a pure blood pool contrast agent that allows for a unique evaluation of the perfusion kinetics of a region of interest.

The Asian Federation of Societies for Ultrasound in Medicine and Biology (AFSUMB) Guidelines for Contrast-Enhanced Endoscopic Ultrasound

The Asian Federation of Societies for Ultrasound in Medicine and Biology aimed to provide information on techniques and indications for contrast-enhanced harmonic endoscopic ultrasound (CH-EUS), and to create statements including the level of recommendation. These statements are based on current scientific evidence reviewed by a Consensus Panel of 15 internationally renowned experts. The reliability of clinical questions was measured by agreement rates after voting. Six statements were made on techniques, including suitable contrast agents for CH-EUS, differences between contrast agents, setting of mechanical index, dual imaging and duration and phases for observation. Thirteen statements were made on indications, including pancreatic solid masses, pancreatic cancer staging, pancreatic cystic lesions and mural nodules, detection of subtle pancreatic lesions, gallbladder sludge and polyps, hepatic lesions, lymph nodes, subepithelial lesions, visceral vascular diseases, guidance of fine needle aspiration and evaluation for local therapy. These international expert consensus guidelines will assist endosonographers in conducting CH-EUS according to evidence-based information.

The safety of echo contrast-enhanced ultrasound in high-intensity focused ultrasound ablation for abdominal wall endometriosis: a retrospective study

Background

We aimed to investigate the efficacy and safety of echo contrast-enhanced ultrasound (CEUS) during high-intensity focused ultrasound (HIFU) ablation therapy for abdominal wall endometriosis (AWE).

Methods

A total of 67 patients with AWE were treated with HIFU ablation, and their demographic characteristics were retrospectively analysed. Blood perfusion of the focal lesion was assessed before the operation, during ablation and after the operation with the use of an ultrasound contrast agent, and the effect of the ultrasound contrast agent on treatment was assessed over a 1-year follow-up period. The degree of symptom relief and adverse effects were evaluated after HIFU ablation.

Results

Eighty-two lesions were ablated in 67 patients. CEUS showed that all lesions were successfully ablated with HIFU. The shrinkage ratio of the lesions significantly increased over the follow-up period. Intermittent pain disappeared at 1 month after the operation, and the patients' pain scores significantly decreased at the 1-year follow-up. The mean [± standard deviation (SD)] lesion volume was 7.64±8.95 cm³ on B-mode ultrasound. The post-HIFU non-perfused volume was 18.34±24.08 cm³, and the rate of massive changes on greyscale imaging was 96.16%±5.44% at 12 months. During the procedure, the main complications were a prickling sensation and tenderness in the treatment area and/or a transient "hot" sensation on the skin. After the procedure, there was no obvious discomfort except for pain. Two patients developed an approximately 1-cm area of skin that exhibited a waxy appearance. Seven patients had haematuria. No severe complications were observed.

Conclusions

Ultrasound contrast agents are effective and safe for evaluating the effect of HIFU ablation on AWE, and this approach provides significant guidance and evaluation benefits for the use of HIFU treatment for AWE without obvious side effects.