Contrast-Enhanced Sonography of the Liver: How to Avoid Artifacts.

Contrast-enhanced sonography (CEUS) is a very important diagnostic imaging tool in clinical settings. However, it is associated with possible artifacts, such as B-mode US-related artifacts. Sufficient knowledge of US physics and these artifacts is indispensable to avoid the misinterpretation of CEUS images. This review aims to explain the basic physics of CEUS and the associated artifacts and to provide some examples to avoid them. This review includes problems related to the frame rate, scanning modes, and various artifacts encountered in daily CEUS examinations. Artifacts in CEUS can be divided into two groups: (1) B-mode US-related artifacts, which form the background of the CEUS image, and (2) artifacts that are specifically related to the CEUS method. The former includes refraction, reflection, reverberation (multiple reflections), attenuation, mirror image, and range-ambiguity artifacts. In the former case, the knowledge of B-mode US is sufficient to read the displayed artifactual image. Thus, in this group, the most useful artifact avoidance strategy is to use the reference B-mode image, which allows for a simultaneous comparison between the CEUS and B-mode images. In the latter case, CEUS-specific artifacts include microbubble destruction artifacts, prolonged heterogeneous accumulation artifacts, and CEUS-related posterior echo enhancement; these require an understanding of the mechanism of their appearance in CEUS images for correct image interpretation. Thus, in this group, the most useful artifact avoidance strategy is to confirm the phenomenon's instability by changing the examination conditions, including the frequency, depth, and other parameters.

Safety findings after intravenous administration of sulfur hexafluoride microbubbles to 463,434 examinations at 24 centers.

OBJECTIVES: We aimed to evaluate the safety of the ultrasound contrast agent sulfur hexafluoride microbubbles in a large group of patients referred for routine contrast-enhanced ultrasound (CEUS). METHODS: A retrospective assessment was made of all patients that received sulfur hexafluoride microbubbles intravenously for CEUS at 24 centers between January 2006 and April 2019. Patient demographic details, examination type, and the dose of sulfur hexafluoride microbubbles administered were recorded with specific adverse events (AEs) documentation tools at each center. All AEs were recorded as serious or non-serious. Non-serious AEs were classified by intensity as mild, moderate, or severe according to ACR criteria. The frequencies of AEs across patient subgroups were compared using the chi-square test. RESULTS: A total of 463,434 examinations were evaluated. Overall, 157 AEs (153 [0.033%] non-serious; 4 [0.001%] serious) were reported after sulfur hexafluoride microbubbles administration, giving an AE frequency of 0.034% (157/463,434). Among the non-serious AEs, 66 (0.014%) were mild, 70 (0.015%) moderate, and 17 (0.004%) severe in intensity. The liver was the most common examination site, presenting an AE frequency of 0.026%. The highest AE frequency (0.092%) was for patients undergoing CEUS for vascular disease. There were no significant gender differences in either the total number or the severity of non-serious AEs (chi-square = 2.497, p = 0.287). The onset of AEs occurred within 30 min of sulfur hexafluoride microbubbles administration in 91% of cases. CONCLUSION: The frequency of AEs to sulfur hexafluoride microbubbles is very low and severe reactions are rare, confirming that sulfur hexafluoride microbubbles are appropriate for routine CEUS applications. KEY POINT: • The frequency of AEs to sulfur hexafluoride microbubbles is very low and severe reactions are rare.

The Multimodal Ultrasound Features of Ovarian Serous Surface Papillary Borderline Tumor.

Aim: Ovarian serous surface papillary borderline tumor (OSSPBT) is very rare. Combined with clinical and pathological features, we aim to investigate the multimodal ultrasound features of OSSPBT. Patients and Methods: There were only 18 patients diagnosed with OSSPBT among the 142 patients who were diagnosed with borderline serous ovarian tumor by pathology from June 2008 to December 2020 in our hospital. Their clinical data, conventional ultrasound, two-dimensional contrast-enhanced ultrasound (2D-CEUS), three-dimensional contrast-enhanced ultrasound (3D-CEUS) characteristics, pathology, and prognosis were retrospectively analyzed. Results: The 18 patients had no specific clinical symptoms. Multiple implantable nodules were found in 8 patients (44.4%), ascites in 13 patients (72.2%), and elevated carbohydrate antigen 125 (CA125) in 15 patients (83.3%). After excluding 2 misdiagnosed patients from 18 patients, 26 tumors in 16 patients (6 unilateral and 10 bilateral) were studied. Conventional ultrasound findings of OSSPBT showed that large solid masses around normal ovary without capsule, and numerous small dense anechoic areas were observed in the parenchyma of the lesion, with strong speckle echo ("blizzard" sign) of varying degrees. The 2D-CEUS and 3D-CEUS showed a normal ovary in the center surrounded by a radial blood supply of OSSPBT with thick and irregular branches. Histopathologically, the papillary fibrous stalk of OSSPBT had a large number of sand bodies and tortuous dilated microvessels. All patients had no recurrence after surgery, and two of them delivered successfully through assisted reproductive technology. Conclusion: OSSPBT has a good prognosis. Its conventional ultrasound is characterized by irregular solid masses surrounding normal ovaries and a large number of "blizzard" signs. It showed low enhancement of eccentricity with irregular radial branches centered on the ovary by CEUS.

Application of multimodal ultrasonography for differentiating benign and malignant cervical lymphadenopathy.

OBJECTIVES: The purpose of this study was to evaluate the diagnostic value of multimodal ultrasonography, including SWE and CEUS, for the differentiation of benign and malignant cervical lymphadenopathy. METHODS: A total of 103 patients with 109 enlarged neck lymph nodes underwent SWE and CEUS. There were 25 hyperplastic lymph nodes, 66 metastatic lymph nodes, and 18 cases of lymphoma. RESULTS: Using 31.6 kPa as the Emax cutoff, the sensitivity, specificity and accuracy of measurements on both benign and malignant cervical lymph nodes were 55.95%, 96%, and 65.2%, respectively. CEUS showed that lymph nodes with reactive hyperplasia mainly exhibited uniform perfusion via the lymphatic hilum (18/25; 72%; P < 0.01). The main manifestation of lymphoma was uniform perfusion through the lymphatic hila (10/18; 55.6%; P < 0.01). Metastatic lymph nodes mainly exhibited uneven perfusion (57/66; 86.4%; P < 0.01). The sensitivity, specificity, and accuracy of multimodal ultrasonography for the diagnosis of benign and malignant cervical lymphadenopathies were 90.5%, 72%, and 86.2%, respectively. CONCLUSIONS: Our findings suggest that multimodal ultrasonography can detect the stiffness (elasticity), perfusion pattern, and characteristics of lymph nodes and is a valuable tool for differentiating between benign and malignant lymphadenopathies.

Advances of Contrast-Enhanced Ultrasonography and Elastography in Kidney Transplantation: From Microscopic to Microcosmic.

Kidney transplantation is the best choice for patients with end-stage renal disease. To date, allograft biopsy remains the gold standard for revealing pathologic changes and predicting long-term outcomes. However, the invasive nature of transplant biopsy greatly limits its application. Ultrasound has been a first-line examination for evaluating kidney allografts for a long time. Advances in ultrasound in recent years, especially the growing number of studies in elastography and contrast-enhanced ultrasonography (CEUS), have shed new light on its application in kidney transplantation. Elastography, including strain elastography and shear wave elastography, is used mainly to assess allograft stiffness and, thus, predict renal fibrosis. CEUS has been used extensively in evaluating blood microperfusion, assessing acute kidney injury and detecting different complications after transplantation. Requiring the use of microbubbles also makes CEUS a novel method of gene transfer and drug delivery, enabling promising targeted diagnosis and therapy. In this review, we summarize the advances of elastography and CEUS in kidney transplantation and evaluate their potential efficiency in becoming a better complement to or even substitute for transplant biopsy in the future.

Differential diagnosis of thyroid nodules through a combination of multiple ultrasonography techniques: A decision-tree model.

The present study aimed to establish a decision tree (DT) model by combining the parameters of conventional gray-scale ultrasonography (US), elastosonography (ES), color Doppler US (CDUS) and contrast-enhanced US (CEUS) for the differential diagnosis of thyroid nodules. A single-center, retrospective study of 321 thyroid nodules was conducted. For 222 nodules, parameters of conventional gray-scale US, CDUS, ES and CEUS were evaluated using univariate logistic regression. Factors for with P<0.10 were further assessed using multivariate logistic regression. Significant factors (P<0.05) were used to establish a DT. The diagnostic accuracy of this DT was then evaluated by its application to the other 99 nodules. After univariate logistic analysis, factors including gender, number of nodules and diffuse disease were excluded, due to P>0.10. The results of multivariate logistic analysis determined that the following factors were required for the DT: Extent of blood flow determined by CDUS (P=0.002), area ratio determined by ES (P=0.033), peak phase patterns determined by CEUS (P<0.001) and micro-calcification determined by conventional gray-scale US (P=0.015). When compared to the pathological or cytological results of 99 nodules, the resulting DT had a sensitivity of 98.6%, specificity of 80.1%, positive predictive value of 93.5% and negative predictive value of 95.5%. These results suggested that a DT combining conventional gray-scale US, ES, CDUS and CEUS may be helpful for differentiating between types of thyroid nodules.

[Characteristics of renal cortical perfusion and its association with renal function among elderly patients with renal artery stenosis].

Objective: To evaluate the characteristics of renal cortical blood perfusion assessed by contrast-enhanced ultrasound (CEUS) in elderly patients with renal artery stenosis (RAS) and its relationship with renal function. Methods: Ninety-three elderly patients diagnosed with RAS, who were admitted in Beijing Hospital during June 2017 and December 2018, were retrospectively enrolled. According to the degree of RAS, 186 renal arteries were divided into normal renal artery group (n=79), mild RAS group (30% to 49%, n=59), moderate RAS group (50% to 70%, n=33), and severe RAS group (70% to 99%, n=15). Renal cortical blood perfusion and renal glomerular filtration rate (GFR) were measured by CEUS and radionuclide renal dynamic imaging. According to the renal GFR, 186 kidneys were divided into normal renal function group (GFR≥35 ml/min, n=42) and mild renal insufficiency group (35 ml/min>GFR≥25 ml/min, n=51), moderate renal insufficiency group (25 ml/min>GFR≥15 ml/min, n=75) and severe renal insufficiency group (GFR<15 ml/min, n=18). The renal cortical blood perfusion time-intensity curve (TIC) and related parameters were analyzed, including the area under the curve (AUC), the slope of the ascending branch (A), the peak intensity (PI), the peak time (TTP) and the mean transit time (MTT), the kidneys of different RAS groups and patients with different renal function groups were analyzed. Pearson correlation analysis was used to evaluate the correlation between renal cortical blood perfusion parameters and renal GFR. Results: (1) Renal cortical blood perfusion and GFR: CEUS showed that parameter A of TIC was significantly reduced, while TTP was prolonged in the mild renal artery stenosis group compared with the normal renal artery group (both P<0.05), GFP was similar between the two groups. Cortical perfusion parameters, such as AUC, A, PI and GFR were significantly lower, while TTP and MTT were significantly prolonged in the moderate and severe renal artery stenosis group than in the normal and mild stenosis groups (all P<0.05). Compared with the moderate stenosis group, AUC, A, PI and GFR were significantly lower while TTP, MTT were significantly prolonged in the severe renal artery stenosis group (all P<0.05). (2) TIC showed that the renal perfusion parameters, AUC, PI and A were significantly lower, while TTP was significantly longer in the mild renal dysfunction group than in the normal renal function group (all P<0.001). The changes aggravated in proportion with renal dysfunction. (3) Correlation between perfusion parameters and GFR: Pearson correlation analysis showed that the AUC (r=0.774, P<0.05), A (r=0.815, P<0.05) and PI (r=0.772, P<0.05) were positively correlated with GFR; serum creatinine level (r=-0.841, P<0.05), renal function grading (r=-0.731, P<0.05), TTP (r=-0.803, P<0.05) and MTT (r=-0.741, P<0.05) were negative correlated with GFR. The degree of stenosis was negatively correlated with GFR (r=-0.427, P<0.05). Conclusion: Cortical perfusion parameters differ significantly among patients with various degree of RAS and renal dysfunction. The renal cortical blood perfusion parameters are correlated with renal GFR.

[Testicular tumors: A diagnostic challenge of imaging]. / Tumeurs testiculaires : les enjeux diagnostiques de l'imagerie.

OBJECTIVES: Reviewing the characterization and the follow-up imaging of testicular tumors. MATERIAL AND METHODS: Literature review (PubMed, Medline) of urological and radiological studies dealing with testicular tumors using keywords: Testicular tumors; Color Doppler ultrasound; US elastography; Magnetic resonance imaging; Contrast enhanced sonography. RESULTS: Ultrasound remains the basic exam for the tumor characterization. Among the other techniques, MRI, elastography, contrast enhanced ultrasound, although still in evaluation, will be increasingly used in the future. The frequency of benign Leydig cell tumors justifies a testicular preservation approach, through improvement of characterization, monitoring or tumorectomy. The follow-up of testicular lesions must be indicated on precise indications: follow-up of the contralateral testicle in the case of germi cell tumor, follow-up by of a supposed benign lesion, such as a small Leydig cell tumor in an infertile patient, follow-up when ultra-sound findings are not sufficiently worrying to require immediate diagnosis but which include pejorative criteria. The tumor markers and the extension screening remain systematic. CONCLUSION: The era of total orchiectomy for any uncertain testicular lesion is over. We try the challenge of characterization, and define management's algorithms based on clinical biological data and suspected nature of the tumor at imaging.

Characteristics of renal cortical perfusion and its association with renal function among elderly patients with renal artery stenosis / 中华心血管病杂志

Objective@#To evaluate the characteristics of renal cortical blood perfusion assessed by contrast-enhanced ultrasound (CEUS) in elderly patients with renal artery stenosis (RAS) and its relationship with renal function.@*Methods@#Ninety-three elderly patients diagnosed with RAS, who were admitted in Beijing Hospital during June 2017 and December 2018, were retrospectively enrolled. According to the degree of RAS, 186 renal arteries were divided into normal renal artery group (n=79), mild RAS group (30% to 49%, n=59), moderate RAS group (50% to 70%, n=33), and severe RAS group (70% to 99%, n=15). Renal cortical blood perfusion and renal glomerular filtration rate (GFR) were measured by CEUS and radionuclide renal dynamic imaging. According to the renal GFR, 186 kidneys were divided into normal renal function group (GFR≥35 ml/min, n=42) and mild renal insufficiency group (35 ml/min>GFR≥25 ml/min, n=51), moderate renal insufficiency group (25 ml/min>GFR≥15 ml/min, n=75) and severe renal insufficiency group (GFR<15 ml/min, n=18). The renal cortical blood perfusion time-intensity curve (TIC) and related parameters were analyzed, including the area under the curve (AUC), the slope of the ascending branch (A), the peak intensity (PI), the peak time (TTP) and the mean transit time (MTT), the kidneys of different RAS groups and patients with different renal function groups were analyzed. Pearson correlation analysis was used to evaluate the correlation between renal cortical blood perfusion parameters and renal GFR.@*Results@#(1) Renal cortical blood perfusion and GFR: CEUS showed that parameter A of TIC was significantly reduced, while TTP was prolonged in the mild renal artery stenosis group compared with the normal renal artery group (both P<0.05), GFP was similar between the two groups. Cortical perfusion parameters, such as AUC, A, PI and GFR were significantly lower, while TTP and MTT were significantly prolonged in the moderate and severe renal artery stenosis group than in the normal and mild stenosis groups (all P<0.05). Compared with the moderate stenosis group, AUC, A, PI and GFR were significantly lower while TTP, MTT were significantly prolonged in the severe renal artery stenosis group (all P<0.05). (2) TIC showed that the renal perfusion parameters, AUC, PI and A were significantly lower, while TTP was significantly longer in the mild renal dysfunction group than in the normal renal function group (all P<0.001). The changes aggravated in proportion with renal dysfunction. (3) Correlation between perfusion parameters and GFR: Pearson correlation analysis showed that the AUC (r=0.774, P<0.05), A (r=0.815, P<0.05) and PI (r=0.772, P<0.05) were positively correlated with GFR; serum creatinine level (r=-0.841, P<0.05), renal function grading (r=-0.731, P<0.05), TTP (r=-0.803, P<0.05) and MTT (r=-0.741, P<0.05) were negative correlated with GFR. The degree of stenosis was negatively correlated with GFR (r=-0.427, P<0.05).@*Conclusion@#Cortical perfusion parameters differ significantly among patients with various degree of RAS and renal dysfunction. The renal cortical blood perfusion parameters are correlated with renal GFR.

Time-intensity curve analysis of contrast-enhanced ultrasound is unable to differentiate renal dysfunction in the early post-transplant period - a prospective study.

BACKGROUND: Contrast enhanced ultrasonography (CEUS) assessment of kidney allografts mainly focuses on graft rejection. However, studies on delayed graft function (DGF) without acute rejection are still lacking. The aim of this study was to build a time-intensity curve (TIC) using CEUS in non-immunological DGF to understand the utility of CEUS in early transplantation. METHODS: Twenty-eight patients in the short-term postoperative period (<14 days) were divided according to the need for dialysis (early graft function [EGF] and [DGF]) and 37 subjects with longer than 90 days follow-up were divided into creatinine tertiles. Time to peak [TTP] and rising time [RT were compared between groups. RESULTS: EGF and DGF were similar, except for creatinine. In comparison to the late group, medullary TTP and RT were shorter in the early group as well as the delay regarding contrast arrival in the medulla (in relation to cortex) and reaching the medullary peak (in relation to artery and cortex). In the late group, patients with renal dysfunction showed shorter temporal difference to reach medullary peak in relation to artery and cortex. CONCLUSIONS: Although it was not possible to differentiate EGF and DGF using TIC, differences between early and late groups point to blood shunting in renal dysfunction.

[Imaging of neoangiogenesis of internal carotid artery's atherosclerotic plaque by contrast-enhanced sonography and histological examination]. / Opredelenie neoangiogeneza ateroskleroticheskoi bliashki vnutrennei sonnoi arterii s pomoshch'iu kontrastno usilennogo ul'trazvukovogo issledovaniia i patogistologicheskogo izucheniia.

Previously, atherosclerosis was considered a disease accompanied exclusively by lipids accumulation. At present time success of fundamental and experimental science confirmed that atherosclerotic process is also associated with neovascularization and prolonged inflammatory response at all stages of atherogenesis from initial manifestations to thrombotic complications. The cause of atherosclerotic plaque instability is neovascularization, which is accompanied by intra-plaque hemorrhage and damage. Complications of carotid arteries atherosclerosis are strokes and transient ischemic attacks. The use of a wide range of diagnostic and pathohistological techniques is required for assessing this pathology. The most promising diagnostic technique is Contrast Enhanced Ultrasonography (CEUS) which allows to assess neovascularization degree in atherosclerotic plaque through the injection of a contrast agents.

[Non-palpable testicular tumors in adults: A management based on imaging? Issue from the French Urologic Association Genital Cancer committee's edit]. / Tumeurs testiculaires non palpables chez l'adulte : vers une prise en charge guidée par l'imagerie ? Une mise au point du Groupe organe génitaux externes du comité de cancérologie de l'Association française d'urologie.

BACKGROUND: Help in management of non-palpable testicular tumors. French Urologic Association Genital cancer committee's Edit. OBJECTIVES: To review their characterization at imaging findings of non-palpable testicular tumors. DOCUMENTARY SOURCES: Literature review (PubMed, Medline) of urological and radiological studies dealing with testicular tumors using keywords: non-palpable/incidental testicular tumors; color Doppler ultrasound; US elastography; magnetic resonance imaging; contrast enhanced sonography; partial surgery. RESULTS: Color Doppler is the basic exam. The size, the presence of microlithts/microlithiasis/macrocalcifications, the vascular architecture are major semiological findings to suggest the benign or the malignant nature of the lesion. Other techniques like multiparametric MRI, contrast-enhanced sonography, sonographic elastography are still in evaluation. The frequency of benign tumors such as Leydig cell tumors lead to preservation management, through improved characterization, monitoring or tumorectomy. LIMITS: Non-randomized study - a very few prospective studies. CONCLUSION: The era of total orchiectomy for any uncertain testicular lesion is over. We try the challenge of characterization, and define management's algorithms based on the suspected nature of the tumors.

Anaphylactic reaction to an ultrasound contrast agent (Lumason) in a patient with systemic mastocytosis.

Severe adverse reactions to ultrasound (US) contrast agents are rare, and only a few cases of anaphylaxis following the administration of US contrast agents have been reported, often without a defined etiology. We present a case of anaphylactic reaction to the injection of an US contrast agent in a patient with systemic mastocytosis, which highlights the disorder as a possible risk factor warranting additional consideration prior to performing a contrast-enhanced US examination.

Solid Renal Tumors Isoenhancing to Kidneys on Contrast-Enhanced Sonography: Differentiation From Pseudomasses.

OBJECTIVES: To estimate the prevalence of solid renal tumors isoenhancing to kidneys in all vascular phases on contrast-enhanced sonography and to investigate whether they can be differentiated from pseudomasses. METHODS: A computer search of the databases of 3 institutions identified 31 patients with pseudomasses and 380 patients with solid tumors investigated with contrast-enhanced sonography. Nineteen of 380 (5%) patients had tumors isoenhancing in all phases. Images and clips of these 19 tumors and the 31 pseudomasses were blindly assessed by 2 radiologists. They were asked to differentiate tumors from pseudomasses based on echogenicity, vascular architecture, and the presence of the medulla. RESULTS: Isoenhancing tumors were clear cell carcinomas (n = 7), angiomyolipomas (n = 3), papillary tumors (n = 3), metastasis (n = 1), and oncocytoma (n = 1). In the 4 nonoperated tumors, the diagnosis was confirmed by progression during the follow-up. There were 3 markedly hyperechoic, 11 mildly hypo/hyperechoic, and 5 isoechoic masses. Most pseudomasses were isoechoic to kidneys (23 of 31), with the medulla identified in 22 of 31 and 15 of 31 by radiologists 1 and 2, respectively. One and 2 pseudomasses were considered tumors by radiologists 1 and 2, respectively. One isoechoic isoenhancing tumor was not identified on contrast-enhanced sonography. Isoenhancing tumors in all phases were differentiated from pseudomasses by combining grayscale and contrast-enhanced sonography (areas under the receiver operating characteristic curve, 0.997 for reader 1; 0.969 for reader 2), with very good inter-reader agreement (weighted κ = 0.81). CONCLUSIONS: In our retrospective study, 5% of solid renal lesions were isoenhancing to kidneys in all phases. Differentiation from pseudomasses was possible by looking at baseline sonographic features and vascular characteristics.

Visibility of focal liver lesions: Comparison between kupffer phase of CEUS with sonazoid and hepatobiliary phase of gadoxetic acid-enhanced MRI.

BACKGROUND: To investigate the agreement between Kupffer phase of Sonazoid contrast-enhanced sonography (CEUS) and hepatobiliary phase of gadoxetic acid-enhanced MRI in the evaluation of focal liver lesions (FLLs). METHODS: One hundred fifty-four FLLs in 154 patients who underwent both Sonazoid CEUS and gadoxetic acid-enhanced liver MRI were included in this retrospective study. FLL visibility on the Kupffer-phase images was graded as one (invisible or isoenhancing), two (vaguely visible or vaguely hypoenhancing), or three (clearly visible or clearly hypoenhancing), and that on the hepatobiliary-phase images of MRI was graded as one (invisible or hyper/isointense), two (vaguely visible or weakly hypointense), or three (clearly visible or strongly hypointense). Pairwise comparison of lesion visibility between the two modalities was performed, and intermodality agreement was assessed. RESULTS: On Kupffer-phase CEUS, 31 (20.1%) lesions were invisible, 17 (11.1%) were vaguely visible, and 106 (68.9%) were clearly visible. On the hepatobiliary-phase MRI, 9 (5.9%) lesions were invisible, 45 (29.2%) were vaguely visible, and 100 (64.9%) were clearly visible. Overall, lesion visibility scores were not significantly different between the two modalities (p = 0.121), but the visibility was significantly better on MRI in smaller lesions. Twenty-eight lesions (18.2%) showed discrepancy in the visibility on CEUS and MRI, and most of the cases (89.7%) were lesions that were invisible on CEUS but visible on MRI. CONCLUSIONS: The overall visibility of FLLs was comparable between the Kupffer phase of Sonazoid-CEUS and the hepatobiliary-phase images of gadoxetic acid-enhanced MRI, with a discrepancy between the two modalities in 18% of the cases. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 45:542-550, 2017.

Discrimination of serous cystadenoma from mucinous cystadenoma in the pancreas with contrast-enhanced ultrasonography: a prospective study in 61 patients.

OBJECTIVES: The preoperative diagnosis between serous cystadenomas (SCAs) and mucinous cystadenomas (MCAs) in pancreas is significant due to their completely different biological behaviors. The purpose of our study was to examine and compare detailed contrast-enhanced ultrasonography (CEUS) images of SCAs and MCAs and to determine whether there are significant findings that can contribute to the discrimination between these two diseases. METHODS: From April 2015 to June 2016, 61 patients (35 patients with SCAs and 26 patients with MCAs) were enrolled in this study. Forty-three cases were confirmed by surgical pathology and 18 by comprehensive clinical diagnoses. All of the CEUS characteristics of these lesions were recorded: size, location, echogenicity, shape, wall characteristics, septa characteristics, and the presence of a honeycomb pattern or nodules. CEUS examinations were performed by two ultrasound physicians. RESULTS: Location (P=0.003), shape (P=0.000), thickness of the wall (P=0.005), the number of septa (P=0.001), and the honeycomb pattern (P=0.001) were statistically significantly different. A head-neck location, a lobulated shape, an inner regular honeycomb pattern, and a thin wall (<3 mm thick) were significant in diagnosing patients with SCAs. When two of these four findings were combined, we could achieve a sensitivity of 71.4% and a specificity of 80.8% to diagnose SCA; when three of these four findings were combined, the specificity was 100%. A body-tail location, a round/oval shape, 0-2 septa, and a thick wall (≥3 mm thick) were most often detected in patients with MCAs. When two of these four findings were combined, we could achieve a sensitivity of 88.5% and a specificity of 65.7% to diagnose MCA; when three of these four findings were combined, the area under the curve (Az) was highest at 0.832, with a sensitivity of 80.8% and a specificity of 85.7%. CONCLUSIONS: The characteristics of tumor location, shape, thickness of the wall, the number of septa, and the honeycomb pattern by CEUS play an important role in the diagnosis of SCAs and MCAs. A combination of these findings can provide better diagnostic performance in the discrimination of SCAs from MCAs.

Value of contrast-enhanced sonography of small hepatocellular carcinoma with sonazoid prior to radiofrequency ablation.

BACKGROUND: We aimed to determine the value of contrast-enhanced sonography (CEUS) with Sonazoid prior to percutaneous radiofrequency ablation (RFA) of small (<3 cm) hepatocellular carcinoma (HCC). METHODS: This prospective study was approved by our institutional review board and informed consent was obtained. The following criteria were used for study enrollment: (1) cirrhotic patients with HCCs found by contrast-enhanced CT or Gd-EOB-DTPA-enhanced MRI; (2) a single HCC <3 cm in longest diameter or multinodular HCCs (<3) with each tumor <3 cm in longest diameter; and (3) indeterminate identification of the index tumor from the surrounding cirrhosis-related pseudolesions on conventional US. Percutaneous RFA was performed under the guidance of CEUS with Sonazoid. The value of CEUS in index tumor detection and targeting was compared with that of concurrently performed conventional US. RESULTS: A total of 38 patients with 43 HCCs (mean size, 1.6 cm; range, 0.5-2.9 cm) were enrolled. The vascular phase of Sonazoid-enhanced ultrasonography showed good tumor enhancement in 30/43 HCCs (70%). The Kupffer phase increased lesion conspicuity and operator's diagnostic confidence in 29 patients with 31 HCCs (31/43, 72%) compared with conventional US. CONCLUSIONS: CEUS with Sonazoid is useful for detection and targeting of small HCC prior to RFA. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 45:383-390, 2017.

Role of Contrast-Enhanced Sonography in the Evaluation of Axillary Lymph Nodes in Breast Carcinoma: A Monocentric Study.

OBJECTIVES: To evaluate the diagnostic performance of contrast-enhanced sonography for characterization of the lymph node status (metastatic or not) in patients with breast carcinomas by comparison with sentinel lymph node biopsy. METHODS: From January to August 2015, 50 female patients with a histologic diagnosis of invasive breast carcinoma were prospectively examined by ipsilateral axillary contrast-enhanced sonography. The test was performed by a single radiologist using an ultrasound system with a broadband 8-12-MHz, 38-mm high-resolution linear transducer. For the target lymph node, we chose a node with a sonographic pattern that was suspicious for malignancy: ie, a longitudinal-to-transverse diameter ratio of less than 2, absence of a central hyperechogenic hilum, or both. In cases with a lack of sonographic signs of malignancy, we evaluated the node with the maximal transverse diameter. Nodes were considered malignant in cases with total absence of contrast enhancement and in those with enhancement alterations. Within 1 week, all patients underwent sentinel lymph node biopsy, followed by a histologic test. RESULTS: The histologic test showed benignity in 22 of 50 sentinel lymph nodes, whereas 28 were metastatic. Among the 22 patients with negative biopsy results, contrast-enhanced sonography showed 18 concordances and 4 false-positives results; among the 28 with positive biopsy results, contrast-enhanced sonography obtained 100% correct characterizations of the axillary status. The sensitivity, specificity, and accuracy were 100%, 82%, and 92%, respectively. CONCLUSIONS: Contrast-enhanced sonography appears to be a method with high accuracy for characterization of axillary lymph nodes, very close to the reference-standard sentinel lymph node biopsy. This technique seems to have overall high sensitivity.

Safety of Sulfur Hexafluoride Microbubbles in Sonography of Abdominal and Superficial Organs: Retrospective Analysis of 30,222 Cases.

OBJECTIVES: The purpose of this study was to investigate the safety of the sulfur hexafluoride microbubble contrast agent SonoVue (Bracco SpA, Milan, Italy) and to implement precautions with the intent of further improving the safety of this contrast agent. METHODS: A total of 30,222 patients undergoing contrast-enhanced sonography of abdominal and superficial organs in our hospital from January 2005 to December 2014 were retrospectively investigated. SonoVue was used as the ultrasound contrast agent. The symptoms and treatments of adverse reactions occurring during the contrast-enhanced sonographic examinations were reviewed and analyzed. RESULTS: No patient died as a result of any adverse reaction. Six patients (0.020%) had adverse reactions of varying degrees, including 2 patients (0.007%) who had signs of early anaphylactic shock (chest tightness, palpitations, sweating, and rapid and weak pulse, followed by cyanosis, a disappearing pulse, and a drop in blood pressure) that improved after active rescue. The remaining 4 patients developed the following: redness and a rash on the arm above the injection site, nasal bleeding and nausea, nausea and vomiting, and back pain with numbness of the lips and limbs. Symptoms in these 4 patients self-resolved after a period of rest. CONCLUSIONS: Contrast-enhanced sonography with sulfur hexafluoride microbubbles had good clinical safety, but rare adverse reactions were observed. A comprehensive emergency plan and rescue measures for adverse reactions should be prepared and made available to minimize the occurrence of negative clinical outcomes.