Use Of Contrast-enhanced Ultrasound Research Articles

Contrast-Enhanced Ultrasound-Guided Radiofrequency Ablation of Renal Tumors.

Although only limited long-term studies evaluating thermal ablation of renal masses have been performed, it appears that thermal ablation has a comparable 5-year success rate to that of partial or total nephrectomy. This technique is often used in patients who are not good candidates for partial or total nephrectomy. Contrast-enhanced ultrasound (CEUS) has been recently approved by the Food and Drug Administration for characterization of focal liver lesions in adults and pediatric patients. CEUS can be used off label for renal applications and has been used for years in Europe and Asia. It has several advantages over contrast-enhanced computed tomography for use as the technique to guide and evaluate efficacy of thermal ablation of renal masses. These include the ability to visualize small amounts of enhancement, repeat dosing to evaluate efficacy of an ablation during a procedure, thin slice thickness, and real-time visualization. Ultrasound contrast is also non-nephrotoxic and non-hepatotoxic, allowing evaluation of patients with renal insufficiency. This article reviews the use of CEUS for the guidance and follow-up of thermal ablative procedures of renal masses.

Quantitative Evaluation of Combretastatin A4 Phosphate Early Efficacy in a Tumor Model with Dynamic Contrast-Enhanced Ultrasound

Combretastatin A4 phosphate (CA4P) is a vascular disrupting agent that rapidly shuts down blood supply to tumors. Early monitoring of tumor perfusion plays a crucial role in determining the optimal strategy to managing treatment and guiding future therapy. The aim of this study was to investigate the potential value of dynamic contrast-enhanced ultrasound (CEUS) in quantitative evaluation of tumor perfusion at an early stage in CA4P therapy. Central and peripheral perfusion of tumors was detected by CEUS pre-treatment (0 h) and 2, 12 and 48 h after CA4P injection. Two perfusion parameters, maximum intensity (IMAX) and time to peak (TTP), were calculated from the time–intensity curve. After CEUS, the efficacy of CA4P was immediately confirmed by immunofluorescence assay and hematoxylin and eosin, Hoechst 33342 and fluorescein isothiocyanate–lectin staining. In CEUS of the center region of tumors, IMAX gradually decreased from 0 to 12 h and regrew at 48 h (p < 0.01). TTP increased only at 2 h. In the peripheral regions, IMAX did not change obviously from 0 to 12 h (p > 0.05) and just increased at 48 h (p < 0.01). The TTP of peripheral regions had the same tendency to vary tendency as that of center regions. In addition, microvascular density (MVD), vascular perfusion and necrotic area of the tumor were quantitatively analyzed. A close correlation between IMAX and MVD was observed in the center areas of tumors (r = 0.72, p < 0.01), whereas the correlation between IMAX and MVD in peripheral areas was weak (r = 0.37, p < 0.01). However, IMAX was positively correlated with tumor perfusion in both center and peripheral areas of tumors (r = 0.82, p < 0.01, and r = 0.63, p < 0.01, respectively). Consequently, IMAX was a reliable indicator of tumor perfusion evaluation by CEUS. The use of CEUS to quantify tumor perfusion could a promising method for the early detection of tumor responses in anti-vascular treatment.

Association between contrast-enhanced ultrasonography and histopathological findings of the metastatic lymph nodes of patients with head and neck cancer: A preliminary study.

The present study aimed to investigate the usefulness of contrast-enhanced ultrasonography (CEUS) and a newly developed analysis software for the detection of microcapillary network distribution in lymph nodes of patients with head and neck cancer (HNC) by comparing the CEUS and histopathological findings. Patients that were diagnosed with HNC between February and September 2016 were enrolled. A total of five patients underwent resection of the primary tumor and neck dissection as their initial treatment. The cervical lymph nodes of these patients were analyzed by CEUS intraoperatively, and their surgical specimens were examined histopathologically. The patients were diagnosed using a combination of physical examination, computed tomography, magnetic resonance imaging and fluorodeoxyglucose-positron emission tomography. For CEUS examination, the microbubble contrast agent Sonazoid™ was injected into a peripheral vein. Video images of the metastatic lymph nodes were captured, and these were subjected to analysis by a newly developed image-analysis software. It was possible to perform intraoperative CEUS of metastatic lymph nodes and obtain accurate matched sections for histopathological examination. Hematoxylin and eosin and cluster of differentiation (CD)34 staining revealed that the software was able to accurately detect capillary vessels in metastatic lymph nodes. However, a number of perfusion deficits were observed in these lymph nodes. In conclusion, by using CEUS with the analysis software, the density and distribution of blood vessels in the metastatic lymph nodes of patients with HNC was revealed. Although the present study was limited and preliminary, it was concluded that this method may be useful to evaluate and to map the capillary vessels in the metastatic lymph nodes of patients with HNC.

Adverse Placental Perfusion and Pregnancy Outcomes in a New Nonhuman Primate Model of Gestational Protein Restriction.

Maternal malnutrition during pregnancy impacts fetal growth, with developmental consequences that extend to later life outcomes. In underdeveloped countries, this malnutrition typically takes the form of poor dietary protein content and quality, even if adequate calories are consumed. Here, we report the establishment of a nonhuman primate model of gestational protein restriction (PR) in order to understand how placental function and pregnancy outcomes are affected by protein deficiency. Rhesus macaques were assigned to either a control diet containing 26% protein or switched to a 13% PR diet prior to conception and maintained on this PR diet throughout pregnancy. Standard fetal biometry, Doppler ultrasound of uteroplacental blood flow, ultrasound-guided amniocentesis, and contrast-enhanced ultrasound (CE-US) to assess placental perfusion were performed mid-gestation (gestational day 85 [G85] where term is G168) and in the early third trimester (G135). Our data demonstrate that a 50% reduction in dietary protein throughout gestation results in reduced placental perfusion, fetal growth restriction, and a 50% rate of pregnancy loss. In addition, we demonstrate reduced total protein content and evidence of fetal hypoxia in the amniotic fluid. This report highlights the use of CE-US for in vivo assessment of placental vascular function. The ability to detect placental dysfunction, and thus a compromised pregnancy, early in gestation, may facilitate the development of interventional strategies to optimize clinical care and improve long-term offspring outcomes, which are future areas of study in this new model.

Contrast-enhanced ultrasound of the kidney: a single-institution experience.

Focal renal masses are typically evaluated by means of triphasic contrast-enhanced CT or MRI scan but use of iodinated contrast or gadolinium is unsuitable for some patients. Contrast-enhanced ultrasound (CEUS) is an imaging alternative in this scenario but has limited availability in Ireland. The aim of the study was to retrospectively evaluate experience with selective use of CEUS for non-invasive characterization of focal renal masses in a tertiary referral institution in Ireland, with a particular focus on cystic renal lesions and the influence of CEUS on final Bosniak classification and treatment outcomes. All cases of renal CEUS between 2009 and 2017 were identified. Imaging history, patient records, histopathology reports, urology conference notes, clinical follow-up details, details of lesion progression or stability on surveillance, biopsy and/or resection details and pre- and post-CEUS Bosniak scores were recorded. Thirty-one patients underwent renal CEUS (7 solid renal lesions, 21 cystic renal lesions and 3 'indeterminate' renal lesions). After CEUS, the CEUS-modified Bosniak score was upgraded in nine patients and downgraded in two patients. All three lesions upgraded from Bosniak III to IV were renal cell carcinomas. One of two lesions downgraded from Bosniak IV to III was resected (cystic nephroma) and the other showed no progression after 19months of surveillance. CEUS is a valuable alternative to CT in assessing complex cystic or solid renal lesions where iodinated CT contrast or gadolinium is inappropriate. CEUS can also refine the Bosniak category of atypical cystic renal lesions and help facilitate treatment decisions.

Usefulness of Contrast-Enhanced Ultrasound in Differentiating Inflammatory Bowel Disease From Colon Cancer

To evaluate the diagnostic performance of contrast-enhanced ultrasound (CEUS) in differential diagnosis of inflammatory bowel disease (IBD) and colon cancer, we enrolled 51 patients with thickened bowel walls (13 with IBD and 38 with colon cancer). Ultrasound and CEUS were performed and both qualitative and quantitative features were analyzed. The intestinal wall stratification was preserved in 63.6% of the IBD group but in only 2.6% of the colon cancer group (p < 0.01). On CEUS, disordered enhancement and heterogeneous enhancement were shown in only 9.1% and 0%, respectively, of the IBD group while in 94.7% and 78.9%, respectively, of the colon cancer group (p < 0.01). For quantitative analysis, compared to IBD, colon cancer showed later enhancement and slower wash-out with less speed to reach peak intensity (p < 0.05). In conclusion, CEUS may prove useful for the differential diagnosis of IBD and colon cancer, but more studies are required.

The Usefulness of Contrast-Enhanced Ultrasound in the Assessment of Early Kidney Transplant Function and Complications.

Objectives: The routine diagnostic method for assessment of renal graft dysfunction is Doppler ultrasound. However, contrast-enhanced ultrasound (CEUS) may provide more information about parenchymal flow and vascular status of kidney allografts. The aim of the study was to assess the effectiveness of CEUS in the immediate post-transplant period, focusing on acute vascular complications. A brief review of available literature and a report of our initial experience is made. Material and methods: 15 kidney transplant (KT) cases with clinical suspicion of acute surgical complication were assessed with CEUS and conventional Doppler ultrasound (US). In addition, bibliographic review was conducted through PubMed, Embase, and ClinicalKey databases. Results: 10% of KT underwent CEUS, useful for detecting vascular complication or cortical necrosis in 4 (26%) and exclude them in 74%. Grafts with acute vascular complications have a delayed contrast-enhancement with peak intensity lower than normal kidneys. Perfusion defects can be clearly observed and the imaging of cortical necrosis is pathognomonic. Conclusions: CEUS is a useful tool in the characterization of renal graft dysfunction with special interest on acute vascular complications after renal transplant. It is a feasible technique for quantitative analysis of kidney perfusion, which provides information on renal tissue microcirculation and regional parenchymal flow. Exploration could be done by a urologist at the patient’s bedside while avoiding iodinated contrast.

The Use of Contrast-Enhanced Ultrasonography for the Characterization of Focal Liver Lesions

Focal liver lesions often occur with or without an underlying liver disease. Contrast-enhanced ultrasonography can aid in characterizing liver lesions, potentially avoiding biopsy and computed tomography procedures. Contrast-enhanced ultrasonography has a high sensitivity and specificity for differentiating characteristics of liver lesions compared with noncontrast sonography. The different contrast characteristics aid in differentiating benign and malignant lesions. Malignant lesions tend to have washout of contrast in the venous phases, whereas benign lesions have hyperenhancement during the venous phases. Therefore, contrast-enhanced ultrasonography should be considered an essential component of the diagnostic process for diagnosing and following focal liver lesions.

Correlation analysis between the parameters of contrast-enhanced ultrasonography in evaluating cervical cancer metastasis and expression of E-cadherin.

The study aims to investigate the correlation between the parameters of contrast-enhanced ultrasonography in evaluating cervical cancer metastasis and expression of E-cadherin. All 120 patients with cervical cancer underwent contrast-enhanced ultrasonography. According to the results of postoperative pathological examination, patients were divided into distant metastasis group (group A), lymph node metastasis without distant metastasis group (group B) and no metastasis group (group C). Expression of E-cadherin in cervical cancer tissues was detected by enzyme-linked immunosorbent assay (ELISA). Correlations between the parameters of contrast-enhanced ultrasonography in evaluating cervical cancer metastasis and expression of E-cadherin were analyzed by Pearsons correlation analysis. Comparison of parameters of contrast-enhanced ultrasonography showed that, the baseline intensity of group A was 11.9±2.2 dB, which was significantly lower than that of group B and C. Baseline intensity of group B was significantly lower than that of group C (13.0±2.4 vs. 15.3±3.6 dB), significant differences were found among three groups (P<0.05). The sensitivity and specificity of the use of enhanced intensity ~83.7 dB in evaluating tumor metastasis of patients with cervical cancer were 82.42 and 79.32%, respectively. Expression level of E-cadherin protein in group A was 0.030±0.003 ng/ml, which was significantly lower than that in group B and C (P<0.05), expression level of E-cadherin protein in group A was significantly lower than that in group C (0.037±0.007 vs. 0.045±0.012 ng/ml), significant differences in the expression level of E-cadherin protein were found among the three groups of cervical cancer patients (P<0.05). Pearsons correlation analysis showed that there was a positive correlation between the baseline intensity of contrast-enhanced ultrasonography and the expression level of E-cadherin (P<0.05), while there was a negative correlation between the enhanced intensity of contrast-enhanced ultrasonography and the expression level of E-cadherin (P<0.05). Contrast-enhanced ultrasonography can be used to determine the tumor metastasis of cervical cancer patients, in addition, the combined use of contrast-enhanced ultrasonography and E-cadherin protein expression can significantly improve the diagnosis and treatment of cervical cancer.

Contrast-enhanced ultrasonography of the liver using SonoVue.

This review focuses on the use of contrast-enhanced ultrasonography (CEUS) with SonoVue (Bracco Imaging) for the diagnosis of focal liver lesions (FLLs), guidance during ablative treatment, and follow-up of liver tumors. Multicenter trials have shown that the performance of CEUS for the characterization of FLLs is similar to that of contrast-enhanced computed tomography or contrast-enhanced magnetic resonance imaging. CEUS with SonoVue has been effectively used for guiding the percutaneous treatment of malignant liver tumors that are invisible or poorly visualized in traditional gray-scale ultrasonography. Postprocedural CEUS may be used to detect and retreat residual viable tissue in the same ablative session. The use of CEUS for the assessment of diffuse liver disease is also discussed.

Quantitative Analysis of Hepatic Microcirculation in Rabbits After Liver Ischemia-Reperfusion Injury Using Contrast-Enhanced Ultrasound

Previous studies have shown that contrast-enhanced ultrasound (CEUS) can be used quantitatively to analyze microcirculation blood perfusion in hepatocellular carcinoma patients. However, limited data have described the application of CEUS in hepatic microcirculation after liver ischemic-reperfusion injury (IRI). The purpose of this study was to explore the use of CEUS quantitatively to assess liver microcirculation after liver IRI. We randomly sorted 45 New Zealand rabbits into 3 groups (15 in each). Group A was a control group in which the rabbits underwent laparotomy alone. In groups B and C, hepatic blood was blocked for 30 min. Simultaneously, rabbits in group C underwent left lateral lobe resection. After 30 min of ischemia, CEUS was conducted after 0 h, 1 h, 6 h and 24 h of reperfusion in the 3 groups. Time-intensity curves (TICs) for CEUS were constructed and quantitative parameters (maximum intensity [IMAX], rise time [RT], time to peak [TTP] and mean transit time [mTT]) were obtained. In addition, serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were computed to estimate liver function before the operation and at 0 h, 1 h, 6 h and 24 h after reperfusion, respectively. Pathologic changes in the liver after reperfusion were also observed. Simultaneously, the correlations between serum transaminase and a variety of quantitative analysis parameters were analyzed. In groups B and C, the IMAX value decreased; whereas RT, TTP, mTT and serum ALT and AST levels increased significantly in comparison with those in group A after 0 h and 1 h of reperfusion. The pathology revealed that erythrocytes were destroyed and microcirculation was disturbed. Then, at 6 h of reperfusion, the IMAX continued to decrease. Additionally, the levels of RT, TTP, mTT and serum ALT and AST increased in comparison with those at 1 h of reperfusion. The pathologic analysis revealed inflammatory cell aggregation and leukocyte infiltration. After 24 h of reperfusion, the IMAX was reduced in comparison with that of the 6-h group. The levels of RT, TTP, mTT and serum ALT and serum AST were increased in comparison with that of the 6-h group. These findings were in accordance with the pathologic analysis. In addition, serum transaminase had a negative correlation with IMAX (p < 0.001) and a positive correlation with RT, TTP and mTT (all p < 0.001). So, in conclusion, the quantitative analysis of CEUS can be used to assess hepatic microcirculation after liver IRI.

Differential diagnosis of complex renal cysts

Cystic renal masses are a common diagnostic challenge in daily imaging. Diagnosis of simple renal cysts usually is not a big problem. Complex renal cysts often create difficulties in differentiating between malignant tumors. Most renal tumors, including cystic, are frequently detected incidentally in patients imaged for other reasons, and the optimal management of these lesions can be challenging. Complex cysts can be either benign (hemorrhagic, infected, posttraumatic) and malignant origin. Modern doctors have variety diagnostic methods to use. The main ones are ultrasound, CT and MRI. However, in some cases, appropriate use of contrast-enhanced ultrasonography, PET/CT, biopsy, and determination of tumor markers. Each of these methods has its advantages and disadvantages, and has a niche for use, depending on the inherent features. The sensitivity and specificity of these methods can effectively use them in practice and apply their individual approach to each patient.

Use of Contrast-Enhanced Ultrasound for Confirmation of Central Venous Catheter Placement: Systematic Review and Meta-analysis.

The purpose of this meta-analysis was to determine the sensitivity, specificity, and positive and negative predictive values of contrast-enhanced ultrasound (US) for confirming the tip location and placement of central venous catheters in adult patients. A systematic review was performed using electronic databases, including MEDLINE, ClinicalTrials.gov, Cochrane, Embase, PubMed, and Scopus. Inclusion criteria were studies conducted on adult patients receiving an internal jugular or a subclavian central venous catheter in the emergency department or intensive care unit. Furthermore, the catheter tip location had to be checked with the use of the agitated saline contrast-enhanced US technique. A total of 2245 articles were screened by title and abstract. Seventeen articles were retrieved and assessed for the predefined inclusion criteria. Four articles and 1 abstract were used in the final analysis. Contrast-enhanced US showed pooled sensitivity of 72% (95% confidence interval, 44%-91%), pooled specificity of 100% (95% confidence interval, 99%-100%), a positive predictive value of 92.1%, and a negative predictive value of 98.5% compared with chest radiography for confirming the placement of central venous catheters. In the setting of central venous catheter placement, postprocedural contrast-enhanced US imaging is a safe, efficient, and highly specific confirmatory test for the catheter tip location compared with chest radiography.

Determination of Skeletal Muscle Microvascular Flowmotion with Contrast-Enhanced Ultrasound

Most methods of assessing flowmotion (rhythmic oscillation of blood flow through tissue) are limited to small sections of tissue and are invasive in tissues other than skin. To overcome these limitations, we adapted the contrast-enhanced ultrasound (CEUS) technique to assess microvascular flowmotion throughout a large region of tissue, in a non-invasive manner and in real time. Skeletal muscle flowmotion was assessed in anaesthetised Sprague Dawley rats, using CEUS and laser Doppler flowmetry (LDF) for comparison. Wavelet transformation of CEUS and LDF data was used to quantify flowmotion. The α-adrenoceptor antagonist phentolamine was infused to predictably blunt the neurogenic component of flowmotion. Both techniques identified similar flowmotion patterns, validating the use of CEUS to assess flowmotion. This study demonstrates for the first time that the novel technique of CEUS can be adapted for determination of skeletal muscle flowmotion in large regions of skeletal muscle.

Diagnostic Performance and Confidence of Contrast-Enhanced Ultrasound in the Differential Diagnosis of Cystic and Cysticlike Liver Lesions.

The aims of this study were to assess the diagnostic performance of contrast-enhanced ultrasound (CEUS) in the characterization of atypical cystic and cysticlike focal liver lesions in comparison with conventional US and to determine whether the use of CEUS can reduce the need for further diagnostic workup. In a 3-year period 48 patients with 50 atypical cystic and cysticlike lesions found at conventional US underwent CEUS. Diagnostic confirmation was obtained in cytohistopathologic examinations, with other imaging modalities, and in follow-up. Overall, there were 24 cystic lesions and 26 cysticlike solid lesions, specifically 32 benign and 18 malignant lesions. The conventional US and CEUS images and cine loops were reviewed by two blinded readers independently. Sensitivity, specificity, area under the ROC curve (Az), and interobserver agreement were calculated. Diagnostic performance improved after review of CEUS examinations by both readers (conventional US Az = 0.781 vs 0.972; CEUS Az = 0.734 vs 0.957). Interreader agreement increased, although slightly (conventional US weighted κ = 0.894; CEUS weighted κ = 0.953). In terms of differential diagnosis, the occurrence of correctly characterized lesions increased after CEUS for both readers (reader 1, 62% to 98%; reader 2, 56% to 96%). The development of low-acoustic-power CEUS has made it possible to identify several imaging features of cystic and cysticlike focal liver lesions that, in association with history and clinical findings, may help to correctly characterize them. Our data indicate the usefulness of CEUS in the evaluation of patients with these lesions.

Intravenous and Intracavitary Use of Contrast-Enhanced Ultrasound in the Evaluation and Management of Complicated Pediatric Pneumonia.

Pediatric pneumonia can be complicated by necrotizing pneumonia or a parapneumonic effusion either in the form of an empyema or a clear effusion. Ultrasonography (US) and computed tomography represent well-established modalities for evaluation of complicated pediatric pneumonia. Contrast-enhanced ultrasound (CEUS) was recently introduced and is gaining increasing acceptance in pediatric imaging. In this case series, we present our initial experience with both intravenous and intracavitary use of CEUS in children with complicated pneumonia. Intravenous CEUS accurately and confidently showed necrotizing pneumonia and delineated pleural effusions, whereas intracavitary CEUS accurately identified the chest catheter location and patency and showed the presence of loculations, suggesting the use of fibrinolytics.

Pilot study: use of contrast-enhanced ultrasonography in feline renal transplant recipients.

Objectives The study aims were to evaluate the feasibility of contrast-enhanced ultrasonography in feline renal transplant recipients in the post-transplantation period and to report findings in a case with presumptive delayed allograft ischemia. Methods Cats were imaged postoperatively using contrast harmonic ultrasonography after a bolus injection of a microbubble contrast medium. Time/mean pixel intensity curves were generated for cortical and medullary regions of interest in the renal allograft in each cat. Arrival time, time to peak, wash-in slope, wash-out slope, mean transit time and renal blood flow were calculated for each area. Results Within the renal cortices of cats without ureteral obstruction 1 day post-transplantation, arrival time was 2.0-6.3 s, time to peak was 3.6-30.1 s, wash-in rate was 2.45-41.14 mean pixel intensity (MPI)/s, wash-out rate was -2.01 to -0.47 MPI/s and blood flow was 6.1-106.5 MPI/s. Ratio mean transit time was 0.29-1.29. Typical cortical and medullary perfusion patterns were observed in these cats. In one cat with delayed graft ischemia followed by presumptive acute transplant rejection, dynamic and heterogeneous cortical and medullary perfusion was demonstrated. Decreases in cortical blood flow were paralleled by elevated serum creatinine. Conclusions and relevance Contrast-enhanced ultrasonography can be used in feline renal transplant recipients and provides both qualitative and quantitative data regarding renal allograft perfusion.

The feasibility of contrast enhanced ultrasonography (CEUS) in the diagnosis of non-cardiac thoracic disorders of dogs and cats

BackgroundThis study describes the feasibility of Contrast Enhanced Ultrasonography (CEUS) in the diagnostic work-up of non-cardiac thoracic disorders of small animals. The second aim is to assess the usefulness of CEUS as a direct guide for sample procedures.ResultsForty animals, 28 dogs and 12 cats, were included in the study. Thoracic disorders included 23 pulmonary lesions [primary carcinoma (14), lymphoma (1), sarcoma (1), histiocytic sarcoma (1), abscess (1) and pneumonia (5)] and 17 mediastinal lesions [lymphoma (8), thymoma (3), mesothelioma (1), melanoma (1), carcinomatous lymphadenopathy (1), mixsosarcoma (1), lipoma (1), and abscess (1)]. The majority of neoplastic pulmonary lesions showed an inhomogeneous distribution of contrast medium, whereas inflammatory lesions had a homogenous distribution with typical pulmonary vessels ramification. The majority of mediastinal malignant lesions showed an inhomogeneous distribution pattern. The lung and mediastinal abscesses had peripheral enhancement of the wall with an avascular center. All cytological and biopsy samples obtained after CEUS were diagnostic. Quantitative analysis, performed in 19/23 pulmonary lesions, showed a statistically significant difference (P < 0.0001) between the arrival time of the malignant (7.27 s - range 4.46–13.52 s) and benign (4.52 s - range 2.87–6.06 s) pulmonary lesions.ConclusionsCEUS may be a useful tool for the evaluation of non-cardiac thoracic lesions. The contrast medium allows for the precise definition of lesion edges, the presence of necrotic areas, and the distribution of pulmonary vessels.Based on our preliminary results, the use of ultrasonographic contrast medium can be recommended for improving the diagnostic usefulness of cytology and biopsy sampling, because CEUS may help to define necrotic areas from viable tissue.

Contrast-Enhanced Ultrasound in the Follow-Up ofEndoleaks after Endovascular Aortic Repair (EVAR).

Endovascular aortic repair (EVAR) has become established in the treatment of abdominal aortic aneurysms and shows potential benefits such as a low perioperative morbidity and a short hospitalization duration. The follow-up after EVAR primarily consists of lifelong postinterventional imaging of the aneurysm size in order to detect complications such as endoleaks or stent dislocation. Computed tomography angiography, an imaging modality that uses ionizing radiation and that relies on a contrast medium which is dependent on thyroid and renal function, is widely used for follow-up. Meanwhile, contrast-enhanced ultrasound (CEUS) has been established as a viable, fast and cost-effective imaging alternative for the follow-up and the detection of endoleaks after EVAR with the additional benefit of being a real-time non-ionizing radiation examination and having comparable or even superior diagnostic performance. This review describes the use of CEUS for follow-up after EVAR and describes the most common pathologies.

Usefulness of Contrast-Enhanced Ultrasonography for Predicting Esophageal Varices in Patients with Hepatitis B Virus (HBV)-Related Cirrhosis.

BackgroundThe aim of this study was to investigate the usefulness of contrast-enhanced ultrasonography (CEUS) in predicting of esophageal varices (EV) and assessing high-risk EV in patients with hepatitis B virus (HBV)-related cirrhosis.Material/MethodsPatients with HBV-related cirrhosis who had undergone endoscopy were prospectively recruited. Hepatic dynamic CEUS was performed. Regions of interest (ROI) were drawn on the hepatic artery, hepatic vein, portal vein, and liver parenchyma to measure the corresponding features, such as arrival times. Spearman’s correlation analysis was used to determine the relations between several dynamic CEUS features and the degree of EV. Receiver operating characteristics (ROC) curves were constructed to investigate the diagnostic performance of CEUS in assessing the presence of EV and high-risk EV.ResultsFifty-eight patients (44 men; mean age 51.3 years) were included in this study. Of these, 18 (31.0%), 12 (20.7%), 11 (19.0%), and 17 (29.3%) of patients had grade 0, 1, 2, and 3 EV, respectively. Grade 2 and grade 3 EV were considered high-risk EV. Among the CEUS features, the area under the ROC curves of intrahepatic transit time (HV–HA, i.e., the difference between hepatic vein arrival time and hepatic artery arrival time) both for assessment of the presence of EV and high-risk EV (0.883 and 0.915, respectively) were larger than the other indices. HV–HA was negatively correlated with the grade of EV. An HV–HA of under 8.2 s indicated the presence of EV and under 7 s indicated high-risk EV.ConclusionsDynamic CEUS imaging is useful in assessing the presence of EV and high-risk EV in patients with HBV-related cirrhosis.