Adverse effects associated with SonoVue®use

Preoperative assessment of fistula-in-ano using SonoVue enhancement during three-dimensional transperineal ultrasound

Background

Accurate preoperative evaluation of fistula-in-ano can guide the choice of surgical procedure and may improve healing rates. This prospective study aimed to evaluate the accuracy of conventional 3D transperineal ultrasound (3D-TPUS) compared with SonoVue (SVE)-enhanced 3D-TPUS for the detection and classification of anal fistula.

Methods

In this prospective study, 3D-TPUS reconstructions were performed before and after SVE enhancement in 60 patients with fistula-in-ano who intended to undergo surgery at the Department of Anorectal Surgery, Qilu Hospital, Cheeloo College of Medicine, Shandong University (P. R. China) between January 2021 and October 2021. Accuracies of anal fistula classification, complexity classification, detection of anal fistula branches, and detection of internal opening between 3D-TPUS and SVE 3D-TPUS were compared based on a reference standard-intraoperative findings.

Results

This study enrolled 60 patients (mean age, 37.1 ± 11.4 years; mean follow-up, 9 ± 3 months). Intraoperative findings showed that the fistula type was intersphincteric in 23 patients (38.3%), trans-sphincteric in 35 (58.3%; 12 high and 23 low), and suprasphincteric in 2 (3.3%). Moreover, 68 internal openings were found. Compared with the accuracy of 3D-TPUS, that of SVE 3D-TPUS was similar in fistula classification [95.0% (57/60) vs 96.7% (58/60), P = 0.392], but significantly higher in internal opening evaluation [80.9% (55/68) vs 97.1% (66/68), P = 0.001], complexity classification [85.0% (51/60) vs 98.3% (59/60), P = 0.018], and detection of fistula branches [70.4% (19/27) vs 92.6% (25/27), P = 0.031].

Conclusions

SVE 3D-TPUS may be a useful examination for patients with perianal fistulae because of its high accuracy and consistency with intraoperative findings, especially in complex fistula-in-ano and difficult cases.

The kinetic quantitative characteristics of non-mass breast lesions with contrast-enhanced ultrasound: a prospective study

OBJECTIVE

To characterize non-mass breast lesions (NML) quantitatively by contrast-enhanced ultrasound (CEUS) and to evaluate its additional diagnostic value based on the Breast Imaging Reporting and Data System (BI-RADS) categories.

METHODS

A prospective study was performed among consecutive patients with NMLs. All lesions were examined by grayscale ultrasound and CEUS and diagnosed on pathology. Standard mammograms were obtained in the patients over 30 years old. Three independent radiologists assessed the features on grayscale ultrasound and mammograms and classified NMLs according to BI-RADS categories. Combined with the quantitative analysis in CEUS, the BI-RADS categories were reassessed, and the sensitivity, specificity, positive-predictive value, negative-predictive value and area under the receiver operating characteristic curve (AUC) were calculated for the evaluation of the diagnostic performance.

RESULTS

30 benign and 24 malignant NMLs were finally enrolled in this study, with ductal carcinoma in situ being the majority of malignant (15/24). Average contrast signal intensity (AI), wash-in rate (WiR) and enhancement intensity at 40 s (I40) were found to be the most efficient kinetic parameters to diagnose malignant NMLs. Combined with the cut-off values of 205.2 for AI, 127.8 for WiR and 136.4 for I40, the diagnostic accuracy was improved (AUC = 0.904), with the sensitivity of 95.8% and the specificity of 70.0%.

CONCLUSION

The results suggested that hyperenhancement and rapid wash-in and wash-out are the characteristics of malignant NMLs. The kinetic analysis using CEUS can reflect hypervascular nature of malignant NMLs, thus improving the diagnostic performance combined with grayscale ultrasound.

ADVANCES IN KNOWLEDGE

In this study, we quantified the enhancement characteristics of non-mass breast lesions with CEUS. We revealed that the combination of CEUS and conventional ultrasound provided higher sensitivity for diagnosing malignant NMLs.

Contrast-Enhanced Ultrasound as a Problem-Solving Modality: Tips and Tricks

ABSTRACT

Contrast-enhanced ultrasound (CEUS) continues to be an ever-growing tool in radiation-free imaging. While it has been widely used in cardiac imaging, CEUS has only recently become an Food and Drug Administration-approved and viable modality for evaluation of abdominal structures. Ultrasound contrast agents are nontoxic, microbubble-based vascular agents and can be used to reliably assess enhancement patterns of various lesions in real time. In particular, it's non nephrotoxic nature makes CEUS a particularly important tool in renal failure patients requiring serial follow-up. This review provides a comprehensive discussion on the utility of CEUS agents, imaging techniques, comparison with traditional cross-sectional imaging modalities, and its application in diagnosing kidney and liver lesions. This pictorial review is illustrated with cases of renal and hepatic lesions that the practicing radiologist should become familiar with as CEUS becomes increasingly popular.

Safety Profile of Musculoskeletal Contrast-Enhanced Ultrasound with Sulfur Hexafluoride Contrast Agent

PURPOSE

Muscle, bone and tendon regeneration depend on the microperfusion of the corresponding tissue which can be quantified with contrast-enhanced ultrasound (CEUS) using sulfur hexafluoride contrast agent (SonoVue®). This study investigated the incidence of adverse events (AEs) in musculoskeletal patients and gives an overview of musculoskeletal CEUS applications.

PATIENTS AND METHODS

Based on 13 studies in a standardized monocentric setting, a total of 2268 CEUS examinations in 764 patients were performed and AEs due to the administration of sulfur hexafluoride contrast agent were classified as either mild, moderate or severe.

RESULTS

No fatal events occurred. AEs were reported in three cases, of which only one was classified as severe and two as mild. The total rate of all AEs was 0.13% and 0.04% for severe AEs.

CONCLUSION

The present analysis confirms the safety of musculoskeletal CEUS using sulfur hexafluoride contrast agent with a lower rate of AEs than that reported for other contrast agents even in elderly patients with concomitant diseases.

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

The aim of this study was to analyze the clinical manifestations of adverse reactions after the use of SonoVue contrast agent from a large retrospective database, and to evaluate the nursing care strategies and the efficacy of standardized procedure for adverse reactions of SonoVue (SPARS).From January 1, 2012 to December 30, 2018, 34,478 cases of contrast-enhanced ultrasonography were performed in our center. The clinical manifestations of adverse reactions after the use of SonoVue contrast agent were identified and analyzed. The nursing care strategies were evaluated and the outcomes of patients with moderate and severe adverse reactions before and after the application of SPARS were compared.Of the 34,478 cases, 40 cases (0.12%) of adverse reactions after the use of SonoVue were identified. Adverse reactions included anaphylatic shock, skin allergies, nausea or vomiting, dizziness or headache, numbness, chest distress, back pain, and local reactions of the injection site. Most of the adverse reactions were mild and self-limited. Only 3 cases of anaphylatic shock and 2 cases of severe rash underwent further treatments. The 3 patients who were managed by SPARS recovered quicker and spent less comparing with the other 2 patients who were not.SonoVue was a safe contrast agent, with few and mostly mild adverse reactions. SPARS may be an efficient way in tackling moderate to severe adverse reactions, although of which the incidence was rare.

CONSUMER PREFERENCES FOR SCANNING MODALITY TO DIAGNOSE FOCAL LIVER LESIONS

OBJECTIVES

Differences in the process of using liver imaging technologies might be important to patients. This study aimed to investigate preferences for scanning modalities used in diagnosing focal liver lesions.

METHODS

A discrete choice experiment was administered to 504 adults aged 25 ≥years. Respondents made repeated choices between two hypothetical scans, described according to waiting time for scan and results, procedure type, the chance of minor side-effects, and whether further scanning procedures were likely to be required. Choice data were analyzed using mixed-logit models with respondent characteristics used to explain preference heterogeneity.

RESULTS

Respondents preferred shorter waiting times, the procedure to be undertaken with a handheld scanner on a couch instead of within a body scanner, no side-effects, and no follow–up scans (p≤.01). The average respondent was willing to wait an additional 2 weeks for the scan if it resulted in avoiding side-effects, 1.5 weeks to avoid further procedures or to be told the results immediately, and 1 week to have the scan performed on a couch with a handheld scanner. However, substantial heterogeneity was observed in the strength of preference for desirable imaging characteristics.

CONCLUSIONS

An average individual belonging to a general population sub–group most likely to require imaging to characterize focal liver lesions in the United Kingdom would prefer contrast–enhanced ultrasound over magnetic resonance imaging or computed tomography. Insights into the patient perspective around differential characteristics of imaging modalities have the potential to be used to guide recommendations around the use of these technologie

What is the role of contrast-enhanced ultrasound in the evaluation of the endoleak of aortic endoprostheses? A comparison between CEUS and CT on a widespread scale

OBJECTIVE

To evaluate the accuracy of contrast-enhanced ultrasound (CEUS) in comparison to CT angiography (CTA) to identify and classify endoleaks following abdominal aortic aneurism repair with endoprosthesis.

MATERIALS AND METHODS

A retrospective analysis of 181 patients treated with EVAR, from September 2009 to September 2014, was performed. Patients were evaluated with CEUS, CTA and angiography in the cases requiring treatment. Sac diameter, sac integrity, identification and classification of endoleaks were taken into consideration. Sensitivity, specificity, accuracy and negative predictive values were considered for each modality of endoleak identification.

RESULTS

Forty-two endoleaks (23.2%; type II: 39 cases, type III: 3 cases) were documented. Sensitivity and specificity of CEUS and CT were, respectively, 97.6 and 90.5, 100 and 100%. In two cases, CEUS was able to better classify endoleaks compared to CT.

CONCLUSIONS

CEUS accuracy to identify endoleaks following EVAR is similar to CT. CEUS should be considered as an effective modality for the long-term surveillance of EVAR because of its capability to correctly classify endoleaks with no ionizing radiation exposure.

Comparative Diagnostic Performance of Contrast-Enhanced ultrasound versus Baseline Ultrasound for Renal Pelvis Lesions

The aim of this study was to assess the relative efficacy of contrast-enhanced ultrasound (CEUS) and baseline ultrasound (B-US) in diagnosing renal pelvic lesions. B-US findings on 58 suspected renal pelvis lesions were examined. The B-US and CEUS results were classified into five grades. Receiver operating characteristic curve analysis was used to compare the diagnostic efficacy of the two imaging modalities. CEUS characteristics of renal pelvis malignancies at different tumor stages and pathologic grades were examined. In the final diagnosis, 29 patients had malignant lesions (27 transitional cell carcinomas, 1 squamous cell carcinoma and 1 renal cell carcinoma) and 29 had benign lesions. On B-US, echogenicity and renal pelvis separation pattern in patients with malignant renal lesions overlapped those of patients with benign lesions. CEUS significantly increased the diagnostic grade of malignant lesions and decreased the grade of benign lesions (p = 0.000). The area under the receiver operating characteristic curve of CEUS was larger than that of B-US (p = 0.030). Enhancement shape and intensity in the wash-in phase markedly differed in lesions of higher tumor stage and higher pathologic grade, compared with lesions of lower stage and grade. In this study, compared with B-US, CEUS had significantly higher diagnostic efficacy in patients with renal pelvis lesions.

Ultrasound imaging of the liver and bile ducts - expectations of a clinician

Since diseases of the liver and bile ducts are common, a clinician is faced by the need to implement an appropriate diagnostic process. It is necessary to apply diagnostic methods that enable appropriate assessment of the most common pathologies of the liver, i.e. fibrosis, steatosis and focal lesions, as well as initial assessment of the bile ducts. These goals can be achieved using ultrasound methods based on conventional sonography, contrast-enhanced sonography and elastography. The assessment of fatty liver and bile duct dilatation using ultrasound reaches satisfactory levels of sensitivity and specificity. The usage of contrast agents enables unambiguous differentiation between benign and malignant focal lesions, frequently allowing them to be identified accurately without the assistance of other imaging modalities. Elastography has enabled reliable assessment of liver fibrosis. Its results are comparable to those of the standard method, i.e. liver biopsy.

Diagnostic performance of contrast-enhanced ultrasound for ovarian cancer: a meta-analysis

This meta-analysis is the first study aimed at assessing the overall diagnostic performance of contrast-enhanced ultrasound for ovarian cancer. PubMed, Embase and Medline databases were systematically searched for relevant articles published up to June 2014. Data were pooled to yield summary sensitivity, specificity, diagnostic odds ratio and receiver operating characteristic curves using Meta-Disc Version 1.4 software. Ten independent studies with 579 ovarian tumors were enrolled in this meta-analysis. The pooled sensitivity, specificity and diagnostic odds ratio statistics were 0.89 (0.83-0.94), 0.91 (0.88-0.93) and 91.70 (41.41-203.05), respectively, and the area under the summary receiver operating characteristic curve was 0.9619 (standard error: 0.0125), all indicating that contrast-enhanced ultrasound has high diagnostic accuracy in differentiation of malignant from benign ovarian tumors.

Contrast-enhanced ultrasound in liver cancer

Contrast-enhanced ultrasound (CEUS) is a sure, noninvasive, repeatable imaging technique widely used in the characterization of benign and malignant liver lesions. The European Federation of Societies for Ultrasound in Medicine and Biology guidelines suggest the typical CEUS features of liver lesions as criteria for the noninvasive diagnosis in cirrhotic and not-cirrhotic patients. The clinical application of CEUS in the liver study is summarized in this review; the contrast-enhanced patterns of the most frequent liver lesions are described (hepatocellular and cholangiocellular carcinoma, liver metastases, hemangioma, focal nodular hyperplasia, adenoma). The role of this imaging technique in the diagnostic algorithm of liver malignancy is illustrated and the CEUS application in hepatologic and oncological settings is depicted.

Quantification of enhancement of renal parenchymal masses with contrast-enhanced ultrasound

The purpose of this study was to investigate the value of quantitative assessment of enhancement in diagnosing renal cell carcinoma (RCC) with contrast-enhanced ultrasound (CEUS). A total of 73 solid renal parenchymal masses underwent both conventional ultrasound and CEUS. We compared the difference in maximum diameters on conventional ultrasound and CEUS between the benign and malignant groups. Enhancement features derived from a time-intensity curve were also analyzed. The diameters of renal cancer were found to be larger on CEUS than on conventional ultrasound (p < 0.05). When cutoff values of 4.74 s for washout time and 8.52% for enhancement intensity at 60 s for diagnosing RCCs were applied, the sensitivity, specificity and area under the receiver operating characteristic curve were 67.3%, 95.2%, 86.5% and 65.4%, 81.0%, 68.4%, respectively. The sensitivity and specificity for these two enhancement characteristics combined as a criterion for differentiating RCCs from benign lesions were 44.0% and 99.1%, respectively. Early washout in the area of maximal intensity in the interior of the lesion and prolonged washout in the whole area of the lesion are specific CEUS manifestations suggestive of RCC.

Heterogeneity in patient diagnostic pathways: an example from contrast-enhanced ultrasound diagnostic scans for focal liver lesions

Background

The UK’s National Institute for Health and Care Excellence (NICE) has recommended contrast-enhanced ultrasound (CEUS) for the characterisation of focal liver lesions where the results of standard unenhanced ultrasound are inconclusive. A further recommendation is for CEUS to replace other imaging modalities. However, little is currently known about the diagnostic pathways in the National Health Service (NHS) followed by patients with potential liver lesions. The aim of this study was to identify the diagnostic pathways for a number of representative hospital trusts and record the clinicians’ views on patient experiences of these processes through a series of semi-structured interviews with UK clinicians (radiologists and sonographers) (N = 7). This study was undertaken in the broader context of a larger research project where the overarching research question is focused on patient preferences for CEUS and other imaging modalities, and how these impact on patient quality of life (QOL).

Results

The results from the semi-structured interviews with UK clinicians revealed that there is a great deal of heterogeneity in diagnostic pathways followed by patients with potential liver lesions which differ both within and between hospitals. In terms of the patient experience, the clinicians believed that a combination of the more patient-friendly ultrasound process, and the fact that scan results are given to patients in 80-90% of cases on the day, as well as the problems inherent to other scan modalities (claustrophobia, anxiety) would lead to patients preferring ultrasound compared with other imaging modalities (CT or MR). However, current clinical practice means that patient choice is virtually non-existent.

Conclusions

The significant variation in diagnostic pathways across the NHS will require further standardisation through local agreements if contrast-enhanced ultrasound is to replace other imaging modalities in characterising focal liver lesions in line with NICE Diagnostics Guidance. The gradual development of patient choice of modalities may necessitate a change of practice in radiology processes.

Application of a second-generation US contrast agent in infants and children--a European questionnaire-based survey

BACKGROUND

No US contrast agent (US-CA) is currently licensed for use in children.

OBJECTIVE

To survey the off-label use in children of a second-generation US-CA.

MATERIALS AND METHODS

Questionnaires were e-mailed to European paediatric radiologists, who were asked about their experience with the second-generation US-CA Sonovue® (Bracco, Milan, Italy). Number of examinations per indication and adverse effects were recorded. Examinations were categorised by intravenous or intracavitary use of US-CA.

RESULTS

Out of 146 respondents, 88 stated that they did not perform contrast-enhanced US in children, but 36 of these (44%) would appreciate paediatric approval. Forty-five centres reported 5,079 examinations in children (age mean: 2.9 years; range: birth-18 years, M/F: 1/ 2.8). The majority (4,131 [81%] in 29 centres) were intravesical applications. The minority (948 [19%] in 30 centres) were intravenous applications. No adverse effects had been recorded from intravesical use. Six minor adverse effects (skin reaction, unusual taste, hyperventilation) had been recorded after five intravenous studies (0.52%).

CONCLUSION

Responses suggest a favourable safety profile of this second-generation US-CA in children. It also demonstrates a demand for such US-CA from paediatric radiologists.

Ileal Crohn's disease: CEUS determination of activity

Transabdominal ultrasound is currently accepted as a clinical first-line tool in the assessment of Crohn's disease activity. During recent years, great improvements have been achieved in ultrasound examination with the introduction of high-frequency transducers, ultrasonographic microbubble contrast agents, and dedicated contrast-specific ultrasound software. Therefore, contrast-enhanced ultrasonography (CEUS) is emerging as one of the most important imaging techniques in the diagnosis and follow-up of patients with ileal Crohn's disease. It is non-invasive and non-ionizing, easily repeatable, well-tolerated by patients and has significant diagnostic accuracy. Moreover, the possibility to monitor response to therapies, describing, and quantifying contrast enhancement behavior by specific software, represents an interesting aspect of its utilization, considering the still open questions about the correct use of immunosuppressive and biological agents. The aim of our review is to provide an updated overview of the role of CEUS in the patients who have an ileal localization of Crohn's disease, defining its qualitative and quantitative features.

Current and potential renal applications of contrast-enhanced ultrasound

The combination of microbubble technology and complementary ultrasound techniques has resulted in the development of contrast-enhanced ultrasound (CEUS) and, although initial clinical applications largely focussed on the liver, these are now becoming more diverse. With regard to the kidney, it is a safe, well-tolerated, and reproducible technique, and in selected cases, can obviate the need for computed tomography or magnetic resonance imaging. A clear advantage is the absence of nephrotoxicity. With respect to the current and potential renal applications, it is a useful technique in the evaluation of pseudotumours, acute pyelonephritis, renal tumours, cystic lesions, vascular insults, and renal transplantation. It may also be of value for monitoring the kidney following anti-angiogenic treatment or nephron-sparing interventional techniques for renal tumours. Assessment of microvascular perfusion using time-intensity curves is also likely to have further far-reaching applications in the kidney as well as other organs.

Diagnosis value of focal liver lesions with SonoVue®-enhanced ultrasound compared with contrast-enhanced computed tomography and contrast-enhanced MRI: a meta-analysis

PURPOSES

This study is aimed at evaluating diagnostic value of focal liver lesions (FLLs) with SonoVue(®)-enhanced ultrasound compared with contrast-enhanced computed tomography (CECT) and contrast-enhanced magnetic resonance imaging (CEMRI).

METHODS

PubMed, EMBASE, and the Cochrane Central Register were searched for English language articles published from January 2000 to May 2011. Histopathologic analysis and/or close clinical and imaging follow-up (except CECT or CEMRI) for at least 6 months were used as golden reference. Sensitivity, specificity, summary receiver operating characteristic (SROC) curves, and area under the curve (AUC) were extracted to test heterogeneity.

RESULTS

In 21 included studies, for the SonoVue(®)-enhanced ultrasound studies, sensitivity was 88% (95% CI 87-90), specificity was 81% (95% CI 79-84), and 38.62 (95% CI 13.64-109.35) for diagnostic odds ratio (DOR); for the CECT studies, sensitivity was 90% (95% CI 88-92), specificity was 77% (95% CI 71-82), and 30.84 (95% CI 11.11-85.61) for DOR; for the CEMRI studies, sensitivity was 86% (95% CI 83-88), specificity was 81% (95% CI 76-85), and 27.63 (95% CI 11.28-67.70) for DOR.

CONCLUSIONS

In comparison, SonoVue(®)-enhanced ultrasound had high pooled sensitivity and pooled specificity. SROC analysis showed the diagnostic value of FLLs with SonoVue(®)-enhanced ultrasound has no significant difference compared with CECT and CEMRI. SonoVue(®)-enhanced ultrasound is highly sensitive and specific in the characterization of FLLs to support an effective diagnostic method.

Diagnostic value of contrast-enhanced ultrasound, computed tomography and magnetic resonance imaging for focal liver lesions: a meta-analysis

The diagnostic performance of contrast-enhanced ultrasound (CEUS), contrast-enhanced computed tomography (CECT) and contrast-enhanced magnetic resonance imaging (CEMRI) was determined in patients with focal liver lesions (FLLs) in a meta-analysis. Meta-Disc version 1.4 was used to describe and calculate sensitivity, specificity, summary receiver operating characteristic (SROC) curves and area under the curve (AUC). In the 25 included studies, the pooled estimate of CEUS studies for sensitivity, specificity and diagnostic odds ratio (DOR) was 87% (95% CI 85-88), 89% (95% CI 87-91) and 78.84 (95% CI 29.40-211.40), respectively. Sensitivity, specificity and DOR were 86% (95% CI 84-88), 82% (95% CI 77-86) and 26.34 (95% CI 8.32-83.39), respectively, for the CECT studies. Sensitivity, specificity and DOR were 85% (95% CI 82-88), 87% (95% CI 83-91) and 48.37 (95% CI 15.87-147.45), respectively, for the CEMRI studies. SROC analysis indicated that the diagnostic value of CEUS for FLLs is not significantly different from that of CECT and CEMRI.

Reply to "Application of contrast-enhanced intraoperative ultrasonography in the decision-making about hepatocellular carcinoma operation"

The use of contrast-enhanced intraoperative ultrasound for hepatocellular carcinoma has been already proposed as a novel technique to stage the disease during surgical resection. In the herein presented “letter to the editor”, the authors underline some important points, which have been raised following paper published in the January issue of World Journal of Gastroenterology.

The acute effect of an echo-contrast agent on right ventricular dimensions and contractility in pigs

BACKGROUND

: The aim of the present study was to examine the effect of the second-generation ultrasound contrast agent (2nd GUCA) SonoVue on right ventricular (RV) dimensions and contractility and to investigate whether a dose-related interaction exists between the contrast agent and RV function.

METHODS

: Twenty-eight pigs were randomly assigned to 3 groups for intravenous administration: a low-dose group (0.5 cc of SonoVue), a high-dose group (1 cc of SonoVue), and a control group (2 cc of normal saline). RV end-diastolic (EDD) and end-systolic dimension (ESD) and pulmonary pressure (PP) were measured, and the fractional shortening (FS%) was calculated before the administration of SonoVue or normal saline and after the return of the RV-EDD or PP to the baseline value. The time to reach maximal RV-EDD or PP value and the time until the return of RV-EDD or PP to the baseline value were also measured.

RESULTS

: Contrast agent infusion was followed by an acute transient increase of RV-EDD, RV-ESD, FS, and PP in both the low-dose and high-dose groups, but the increase was greater in the high-dose group. FS and PP did not change significantly in the control group. A dose-dependent delay in the time from baseline to maximum RV-EDD and PP was detected in the high-dose group (P < 0.001 for both) as well as a delay in the return from maximum to the baseline values (P < 0.001 for both).

CONCLUSIONS

: Administration of the 2nd GUCA SonoVue is associated with an acute, transient, dose-dependent RV dilatation and an increase in pulmonary pressure with a consequent impact on RV contractility.

Microbubble ultrasound contrast agents: an update

Microbubble contrast agents for ultrasound (US) have gained increasing interest in recent years, and contrast-enhanced US (CEUS) is a rapidly evolving field with applications now extending far beyond the initial improvements achieved in Doppler US. This has been achieved as a result of the safe profile and the increased stability of microbubbles persisting in the bloodstream for several minutes, and also by the availability of specialized contrast-specific US techniques, which allow a definite improvement in the contrast resolution and suppression of signal from stationary tissues. CEUS with low transmit power allows real-time scanning with the possibility of prolonged organ insonation. Several reports have described the effectiveness of microbubble contrast agents in many clinical applications and particularly in the liver, spleen, and kidneys. CEUS allows the assessment of the macrovasculature and microvasculature in different parenchymas, the identification and characterization of hepatic and splenic lesions, the depiction of septal enhancement in cystic renal masses, and the quantification of organ perfusion by the quantitative analysis of the echo-signal intensity. Other fields of application include the assessment of abdominal organs after traumas and the assessment of vesico-ureteral reflux in children. Finally, tumor-targeted microbubbles make possible the depiction of specific biologic processes.

Contrast-enhanced ultrasonography to detect liver metastases : a prospective trial to compare transcutaneous unenhanced and contrast-enhanced ultrasonography in patients undergoing laparotomy

BACKGROUND/AIMS

The advent of contrast-enhanced ultrasound (CEUS) has called into question the efficacy of standard ultrasonographic techniques. In this study, we evaluated B-mode and color-duplex imaging and CEUS in the detection of liver metastases, using intraoperative and histological findings as a reference.

MATERIALS AND METHODS

Before laparotomy, 108 patients suspected of having liver metastases were prospectively examined with B-mode and color-duplex imaging, followed by contrast-enhanced ultrasound (2.4 ml SonoVue). Patients with unresectable tumors (n=8) were excluded from the analysis. The sonographic diagnosis in the remaining 100 patients was compared to the intraoperative and histological findings.

RESULTS/FINDINGS

CEUS improved the sensitivity for detecting liver lesions from 56.3% (B-mode) to 83.8% (CEUS) (p=0.004). In particular, the contrast agent led to an improvement in ultrasonographic detection in the following cases: nodular metastases smaller than one centimeter; after adjuvant chemotherapy; for tumors near the surface of the liver; and for lesions situated around the ligamentum teres.

INTERPRETATION/CONCLUSIONS

CEUS provides significant improvement in the detection of liver metastases, and should therefore, be performed routinely in the surveillance of cancer patients.