Contrast-enhanced Ultrasound Studies Research Articles

Ultrasound and cytopathological characteristics of thyroid tumours of uncertain malignant potential - from diagnosis to treatment.

The latest World Health Organization (WHO) classification from 2022 distinguishes the division of low-risk thyroid neoplasms such as non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP), follicular tumour of uncertain malignant potential (FT-UMP), and well-differentiated tumour of uncertain malignant potential (WDT-UMP). The final diagnosis is made postoperatively according to histopathologic results. The aim of the study was the assessment of ultrasonographic and cytopathological features of borderline lesions to predict low-risk tumours preoperatively and plan the optimal treatment for that group of patients. A total of 35 patients (30 women; 5 men), aged 20-81 years with a mean age of 49 years, were enrolled in the study. The study evaluated 35 focal lesions of the thyroid gland, classified as low-risk neoplasms according to the WHO 2022 classification: FT-UMP (n = 21), NIFTP (n = 7), and WDT-UMP (n = 7). Ultrasonographic features of nodules including contrast-enhanced ultrasound (CEUS) and elastography were assessed by 2 specialists, and the risk of malignancy was evaluated according to EU-TIRADS-PL classification. Of the 35 focal thyroid lesions, most were categorised as low or intermediate risk of malignancy according to EU-TIRADS-PL, with dominant category 3 [n = 13 (37.2%)] and category 4 [n = 15 (42.8%)]. High-risk category 5 was assessed in 7 lesions (20%). In cytopathology nodules were categorised as follows (Bethesda System TBSRTC 2023): Bethesda II (n = 4), Bethesda III (n = 2), Bethesda IV (n = 25), Bethesda V (n = 3), and Bethesda VI (n = 1). In the CEUS study, contrasting patterns dominated compared to the surrounding parenchyma, such as enhancement equal to the parenchyma (66.6%) or intense (28.5%), heterogeneous (61.9%), centripetal (42.8%), or diffuse (57.1%) with fast (33.3%) or compared to parenchyma contrast wash-in (42.8%) and its fast (33.3%) or comparable to thyroid parenchyma wash-out (52.3%). The study indicates that lesions with uncertain malignant potential typically present features suggesting low to intermediate risk of malignancy based on EU-TIRADS-PL classification, with dominant cytopathologic Bethesda IV category. However, 20% of lesions were assessed tas EU-TIRADS-PL category 5. Low-risk tumours, including NIFTP, FT-UMP, and WDT-UMP, require careful observation and monitoring post surgical treatment due to their potential for recurrence and metastasis. The preoperatively prediction of borderline tumour may play an important role in proper treatment and follow-up.

Contrast-Enhanced Ultrasound of the Chest in Children and Adolescents: A Pilot Study for Assessment of Added Diagnostic Value.

To determine the added diagnostic value of contrast-enhanced ultrasound (CEUS) in pediatric chest abnormalities by comparing interpretation of CEUS studies and confidence level to conventional US studies. CEUS studies in patients with a variety of clinically suspected chest abnormalities performed between 2016 and 2020 were reviewed and compared to same-day conventional US studies. Examinations were independently interpreted by 4 radiologists blinded to clinical and other imaging data. Rater confidence was classified as low, moderate, or high. Diagnostic accuracy was determined by comparing image interpretation to patient outcome as the ground truth. Interobserver agreement was also assessed. Sixteen patients (10 male) with 18 CEUS studies were included. Median rater agreement with ground truth was significantly higher for CEUS (100%) than conventional US (50%; P = .004). Median rater confidence was high (3.0) for CEUS, and low-moderate (1.5) for conventional US (P < .001). CEUS sensitivity (54.6-81.8%) and specificity (63.4-100.0%) were greater than conventional US (45.5-72.7% and 12.5-63.5%, respectively). CEUS false positives (0-4) and false negatives (2-5) were fewer than conventional US (4-7 and 3-6, respectively). Except for one rater pair where agreement was substantial (κ = .78, P < .01), inter-rater agreement for CEUS for all other rater pairs was nonsignificant (κ = .25-0.51, P ≥ .07). Agreement for conventional US was moderate and statistically significant for 3 rater pairs (κ = .55-0.78) and nonsignificant for the remaining 3 rater pairs (P ≥ .06). CEUS adds diagnostic value to the assessment of a variety of chest abnormalities. The data support further evaluation of the role of CEUS as a non-invasive, problem-solving technique in children.

Diagnostic performance of magnetic resonance imaging and contrast-enhanced ultrasound in differentiating intrahepatic cholangiocarcinoma from hepatocellular carcinoma: a meta-analysis.

To compare the diagnostic ability between magnetic resonance imaging (MRI) and contrast-enhanced ultrasound (CEUS) in distinguishing intrahepatic cholangiocarcinoma (ICC) from hepatocellular carcinoma (HCC). Original studies reporting the diagnostic accuracy of MRI and CEUS in differentiating ICC from HCC were identified in PubMed and EMBASE databases. Histopathological examination was used as the reference standard for tumor diagnosis. Study quality was assessed using QUADAS-2 scale. Data were extracted to calculate the pooled diagnostic sensitivity, specificity, and diagnostic odds ratio (DOR) using a bivariate random-effects model, as well as the area under the curve (AUC). Sensitivity analysis, subgroup analysis, meta-regression, and investigation of publication bias were also performed. A total of 26 studies with 28 data subsets (18 on MRI, 10 on CEUS) were included, consisting of 4169 patients with 1422 ICC lesions and 2747 HCC lesions. Most MRI studies were performed at 3T with hepatobiliary agents, and most CEUS studies used SonoVue as the contrast agent. In MRI, the pooled sensitivity, specificity, DOR, and AUC in distinguishing ICC from HCC were 0.81 (0.79, 0.84), 0.90 (0.88, 0.91), 41.47 (24.07, 71.44), and 0.93 (0.90, 0.96), respectively. The pooled sensitivity, specificity, DOR, and AUC of CEUS were 0.88 (0.84, 0.90), 0.80 (0.78, 0.83), 42.06 (12.38, 133.23), and 0.93 (0.87, 0.99), respectively. Subgroup analysis and meta-regression analysis demonstrated significant heterogeneity among the studies associated with the type of contrast agent in MRI studies. No publication bias was found. Both MRI and CEUS showed excellent diagnostic performance in differentiating ICC from HCC. CEUS showed higher pooled sensitivity and MRI showed higher pooled specificity.

Washout appearance of hepatocellular carcinomas using standardized contrast-enhanced ultrasound (CEUS) including an extended late phase observation - Real-world data from the prospective multicentre DEGUM study.

Non-invasive diagnosis of hepatocellular carcinoma (HCC) in contrast-enhanced ultrasound (CEUS) is based on the combination of arterial phase hyperenhancement (APHE) and subsequent late (>60 seconds) and mild contrast washout (WO). Whereas APHE is seen in the majority of HCC, wash-out pattern may vary in onset and intensity. In some HCC lesions, even no washout is seen at all. Our prospective multicentre DEGUM HCC CEUS study aimed at identifying typical and atypical washout appearance of HCC in a real-life setting. High-risked patients for HCC with focal liver lesions upon B-mode ultrasound were recruited prospectively. In a multicentre real-life setting, a standardised CEUS examination including an extended late phase up to 6 minutes was performed. CEUS patterns of HCC were recorded, and onset and intensity of washout appearance were assessed with respect to patient and tumour characteristics. Histological findings served as reference standard. In 230/316 HCC (72.8%), a CEUS pattern of APHE followed by WO was observed. In 158 cases (68.7%), WO was typical (onset > 60 seconds, mild intensity). 72 cases (31.3%) showed marked and / or early WO, whereas in 41 HCCs (13%), APHE was followed by sustained isoenhancement.Atypical WO upon CEUS was associated with macroinvasion of the liver vessels, portal vein thrombosis and diffuse growth pattern, but not tumour size and histological grading. In a prospective multicentre real-life setting, APHE is followed by atypical washout appearance or no washout at all in almost half of the HCCs with APHE. The examiner has to bear in mind that in spite of a characteristic APHE in HCCs, washout appearance can be atypical in CEUS, especially in HCCs with macrovascular invasion or diffuse growth pattern.

Evaluation of Soft-Tissue Hematomas With Real-Time, Contrast-Enhanced Ultrasound: A Pilot Study With Preliminary Findings.

In this study, we investigated the feasibility of using contrast-enhanced ultrasound (CEUS) to detect active hemorrhage in patients presenting with soft-tissue hematomas. Adult patients with clinically suspected, actively bleeding hematomas were prospectively enrolled. Contrast-enhanced ultrasound was used to assess for contrast extravasation. Ultrasound results were compared with those of multidetector computed tomographic (MDCT) imaging, operative findings, and clinical course. Sixteen patients (9 women, 7 men; mean age, 69 [SD, 13] years) were enrolled. Thirteen patients underwent MDCT imaging during their initial visit, and for 11, CEUS and computed tomography (CT) findings were concordant. The remaining patients had a negative CEUS study that was consistent with their clinical course. In 8 patients, CT imaging showed active extravasation (6 arterial, 1 indeterminate, 1 slow venous). Contrast-enhanced ultrasound and CT findings were concordant for all cases of arterial bleeding. For 1 patient, CEUS provided superior diagnostic information by identifying a pseudoaneurysm. The 2 discrepant patient cases had a ≥3-hour delay between CT and CEUS, and in 1 patient, CEUS was limited by body habitus. The second patient had no active bleeding identified in the operating room. Compared with CT, CEUS had a sensitivity and specificity of 75% and 100%, respectively, and positive and negative predictive values were 100% and 71%, respectively. Diagnostic accuracy was 85% in this limited study. Contrast-enhanced ultrasound is a promising alternative to MDCT in select patients and may sometimes provide superior clinical information. Limiting factors are large hematoma size, unfavorable anatomic location, and body habitus.

Contrast‐enhanced ultrasound studies registered on ClinicalTrials.gov: A cross‐sectional analysis of characteristics, early discontinuation, and reporting results

A data set containing all contrast-enhanced ultrasound clinical studies from ClinicalTrials.gov registered was downloaded. Then, a cross-sectional descriptive study of clinical contrast-enhanced ultrasound studies was conducted. Cox and logistic regression of early discontinuation and reported results, respectively, were also performed. A total of 225 studies were identified; 174 were interventional and 51 were observational. Regarding the outcomes measure, 175 (77.78%) were diagnosis-oriented, and the remaining 50 (22.22%) were interventional radiology studies. The most common regions of interest were abdominal (56%), superficial (14.22%), or vascular (7.11%) organs. As of the contrast agents, SonoVue/Lumason (39.11%) was most frequently used, followed by Definity (20.89%) and Sonazoid (8.89%). Of all contrast-enhanced ultrasound studies, 32 (14.22%) were discontinued early, and 29 (12.89%) completed studies reported their results. Cox regression analysis revealed that a large sample size and US registration were factors reducing early discontinuation risk. Among completed studies, factors associated with reported results were industry funding and US registration. The findings suggest that the number of contrast-enhanced ultrasound studies has grown over time, but is still small. Developing new advancements in contrast-enhanced ultrasound will require a concerted effort to increase the quality and quantity of clinical studies in this field.

Can contrast-enhanced ultrasound differentiate the type of hepatic echinococcosis: cystic echinococcosis or alveolar echinococcosis?

BackgroundHepatic echinococcosis (HE) is a zoonotic disease caused by Echinococcus, and Echinococcus granulosus and E. multilocularis are the most common, causing cystic echinococcosis (CE) and alveolar echinococcosis (AE), respectively. Contrast-enhanced ultrasound (CEUS) is an imaging technique which has been recommended for identifying focal lesions in the liver. However, the effect of CEUS on the differentiation of hepatic echinococcosis type remains unclear.MethodsTwenty-five patients with 46 HE lesions confirmed by histopathology in our hospital from December 2019 to May 2022 were reviewed by conventional ultrasound (US) and CEUS examinations, respectively. After US was completed, the CEUS study was performed. A bolus injection of 1.0–1.2 ml of a sulfur hexafluoride-filled microbubble contrast agent (SonoVue®) was administered. The images and clips of the lesions by US and CEUS were reviewed retrospectively. The lesions detected using US were evaluated including the location, size, morphology, margin, internal echogenicity and the internal Doppler signal. The lesions detected using CEUS were evaluated including the enhancement degree, enhancement pattern and enhancing boundary in different phases. The diagnoses of lesions by US or CEUS were respectively recorded. By taking the histopathology as the gold standard, the paired Chi-square test was performed with statistical software (IBM SPSS; IBM Corp., Armonk, NY, USA), and the results of differentiation of HE type by US and CEUS were statistically analyzed.ResultsA total of 46 lesions were involved in 25 patients, including 10 males (40.0%) and 15 females (60.0%) aged 15–55 (42.9 ± 10.3) years. By histopathology, 24 lesions of nine patients were diagnosed as CE and 22 lesions of 16 patients were diagnosed as AE. Among the 46 HE lesions, compared with histopathological examination, the accuracy rate was 65.2% and 91.3% in US and CEUS findings, respectively. Among the 24 CE lesions, 13 lesions were correctly differentiated by US, and 23 by CEUS. The difference between US and CEUS was statistically significant (Chi-square test, {chi }^{2} = 8.10, df = 23, P < 0.005). Among the total 46 HE lesions, 30 lesions were correctly differentiated by US, and 42 by CEUS. The difference between US and CEUS was statistically significant (Chi-square test, {chi }^{2} = 10.08, df = 45, P < 0.005).ConclusionsCEUS is a more effective technique than US for differentiating the type of HE between CE and AE. It could be a reliable tool in the differentiation of HE.

Intra- and Inter-Observer Variability of Quantitative Parameters Used in Contrast-Enhanced Ultrasound of Kidneys of Healthy Cats.

Contrast-enhanced ultrasound (CEUS) is a non-invasive imaging technique which allows qualitative and quantitative assessment of tissue perfusion. Although CEUS offers numerous advantages, a major challenge remains the variability in tissue perfusion quantification. This study aimed to assess intra- and inter-observer variability for quantification of renal perfusion. Two observers with different levels of expertise performed a quantitative analysis of 36 renal CEUS studies, twice. The CEUS data were collected from 12 healthy cats at 3 different time points with a 7-day interval. The inter- and intra-observer agreement was assessed by the intraclass correlation coefficient. Within and between observers, a good agreement was demonstrated for intensity-related parameters in the cortex, medulla, and interlobular artery. For some parameters, ICCinter was considerably lower than ICCintra, mostly when the ROI encompassed the entire kidney or medulla. With the exception of time to peak (TTP) and mean transit time (mTTI), time-related and slope-related parameters showed poor agreement among observers. In conclusion, it may be advised against having the quantitative assessment of renal perfusion performed by different observers, especially if their experience levels differ. The cortical mTTI seemed to be the most appropriate parameter as it showed a favorable inter-observer agreement and inter-period agreement.

Transtemporal brain contrast-enhanced ultrasound in children: preliminary experience in patients without neurological disorders.

To evaluate the use of transtemporal brain contrast-enhanced ultrasound (CEUS) to assess cerebral blood perfusion in a cohort of children without neurological disorders. We included pediatric patients who were undergoing a clinically-indicated CEUS study. Brain scans were performed with a Siemens Sequoia scanner and a 4V1 transducer, that was placed on the left transtemporal bone. Brain scans were performed simultaneously with the images of the clinically-indicated organ of interest. Qualitative and quantitative analysis was performed to evaluate the hemispherical blood flow at the level of the midbrain during the wash-in and wash-out phases of the time-intensity curve. Clinical charts were reviewed to evaluate post-CEUS adverse events. Five patients were evaluated (mean age 5.8 ± 5.1years). Qualitatively, more avid enhancement in the midbrain than the cortex was observed. Structures depicted ranged between the centrum semiovale at the level of the lateral ventricles and the midbrain. A quantitative analysis conducted on four patients demonstrated less avid perfusion on the contralateral (i.e. right) side, with a mean left/right ratio ranging between 1.51 and 4.07. In general, there was a steep positive wash-in slope starting at approximately 10s after contrast injection, reaching a peak intensity around 15-26s on the left side, and 17-29s on the right side. No adverse events were reported. Transtemporal brain CEUS is feasible and safe in the pediatric population and allows qualitative and quantitative assessment of cerebral perfusion.

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

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

Intraoperative contrast-enhanced ultrasound for intramedullary spinal neoplasms: patient series

BACKGROUNDPrimary intramedullary spinal tumors cause significant morbidity and death. Intraoperative ultrasound as an adjunct for localization and monitoring the extent of resection has not been systematically evaluated in these patients; the effectiveness of intraoperative contrast-enhanced ultrasound (CEUS) remains almost completely unexplored.OBSERVATIONSA retrospective case series of patients at a single institution who had consented to the off-label use of intraoperative CEUS was identified. Seven patients with a mean age of 52.8 ± 15.8 years underwent resection of intramedullary tumors assisted by CEUS performed by a single attending neurosurgeon. Histopathological evaluation revealed 3 cases of hemangioblastoma, 1 case of pilocytic astrocytoma, 2 cases of ependymoma, and 1 case of subependymoma. Contrast enhancement correlated with gadolinium enhancement on preoperative magnetic resonance imaging. Intraoperative CEUS facilitated precise lesion localization and myelotomy planning. Dynamic CEUS studies were useful in demonstrating the blood supply to lesions with a dominant vascular pedicle. Regardless of contrast uptake, the differential enhancement between spinal cord tissue and neoplasm assisted in determining interface boundaries.LESSONSIntraoperative CEUS constitutes a useful adjunct for the intraoperative delineation of contrast-enhancing intramedullary tumors and in vivo confirmation of gross-total resection. Systematic investigation is needed to establish the role of CEUS for resection of intramedullary spinal tumors of various pathologies.

Comparison of Contrast-Enhanced Ultrasound Versus Magnetic Resonance Imaging in the Detection and Characterization of Uterine Leiomyomas.

Uterine fibroids are common findings in women with pelvic pain and abnormal uterine bleeding. The reference standard test in the pretreatment evaluation of fibroids is contrast-enhanced magnetic resonance (MR) imaging. This study compared the number, size, location, and enhancement of uterine fibroids identified by contrast-enhanced ultrasound (CEUS) and MR. The aim of this study was to demonstrate that CEUS performs similarly to MR and could be used as an alternative imaging modality. In this prospective observational study, 26 women underwent transabdominal CEUS and MR examinations. Blinded to the original clinical MR interpretations, 2 readers reviewed the MR and CEUS studies for each patient. The number, size, location, and enhancement of each fibroid per patient were reported by MR and CEUS. A Pearson correlation coefficient was calculated for the number of fibroids identified by each modality. In total, 126 fibroids were imaged: 115 (91.3%) were observed on both examinations; 9 (7.1%) were observed by MR only; and 2 (1.6%) were observed by CEUS only. A high correlation was found between the modalities for the number of fibroids identified per patient (r = 0.97; P < .001). There was also no significant difference between the modalities for each patient in the fibroid number, size, location, or enhancement. These findings suggest that transabdominal CEUS may represent an alternative to MR in pretreatment evaluation of uterine fibroids and could serve as a test of choice in patients with a contraindication to MR.

Homogeneity Parameter in Contrast-Enhanced Ultrasound Imaging Improves the Classification of Abnormal Cervical Lymph Node after Thyroidectomy in Patients with Papillary Thyroid Carcinoma.

Objective To explore the conventional and contrast-enhanced ultrasound (CEUS) features of cervical lymph node metastasis (CLNM) in papillary thyroid carcinoma (PTC) patients postoperatively and analyze its pathological basis. Materials and Methods Conventional and CEUS were performed in 86 abnormal cervical lymph nodes (ACLNs) from 56 PTC patients who had received thyroidectomy. Then, fine-needle aspiration (FNA) was taken to confirm pathological results, a multivariate analysis was performed to correlate the sonographic features of the CLNM, and then an equation for CLNM was established. Results Fifty-four lymph nodes were confirmed to be metastasis of PTC by FNA. Intensity at peak time, homogeneity, and color flow patterns, cystic change, or microcalcification and echogenicity were significantly associated with CLNM. Multivariate analysis showed three strongest features (homogeneity, intensity of peak, and cystic change or calcification) to be significantly associated with the evidence of CLNM. Then, the equation was established with the following significant predictive factors: P = 1/1 + exp∑[−3.213 + 2.77 ∗ cystic or calcification + 0.13 ∗ CDFI patterns + 3.65 ∗ homogeneity + 2.43 ∗ intensity at peak time]. Conclusion Depiction of a heterogeneous hyperenhancement of cervical lymph nodes within CEUS studies and cystic change or microcalcification in conventional ultrasound were identified as predictive for metastatic lymph node invasion, and the equation was more accurate for predicting CLNM compared to single B-mode ultrasound and CEUS feature.

Contrast-enhanced ultrasound in the diagnosis of pediatric focal nodular hyperplasia and hepatic adenoma: interobserver reliability.

Focal nodular hyperplasia and hepatic adenoma are rare liver tumors in which specific features on contrast-enhanced ultrasound (US) have been reported but are little known in children. To assess the interobserver agreement in diagnosing and differentiating focal nodular hyperplasia and hepatic adenoma in children using established adult contrast-enhanced US characteristics. Thirty children with a definite or probable diagnosis of focal nodular hyperplasia or hepatic adenoma on magnetic resonance imaging (MRI)/histology who underwent contrast-enhanced US studies were included. Typical and additional contrast-enhanced US features of focal nodular hyperplasia and hepatic adenoma were included. The lesions were classified as definite/probable focal nodular hyperplasia, definite/probably hepatic adenoma or unclassified. The interobserver kappa of contrast-enhanced US characteristics was calculated. Focal nodular hyperplasia and hepatic adenoma in children demonstrate contrast-enhanced US characteristics similar to those in adults. Among the nine lesions with confirmed histological diagnosis, correct diagnosis was made in 7 (77.8%) based on contrast-enhanced US criteria. Two lesions were unclassified by both observers due to a mixed arterial filling pattern. Interobserver kappa for contrast-enhanced US diagnosis was 0.64 (P<0.0001). There is a good interobserver kappa for separating focal nodular hyperplasia from hepatic adenoma in children using established adult contrast-enhanced US features.

[CEUS-application possibilities in the musculoskeletal system].

Contrast-enhanced ultrasound (CEUS) offers easily accessible visualization and quantification of the skeletal muscle microcirculation and other tissues in vivo and in real-time with almost no side effects. The aim of this review is to present the increasing number of musculoskeletal CEUS applications. CEUS applications regarding the musculoskeletal system include applications at bone and joints extending beyond the visualization of only the muscular microcirculation. Besides basic muscle physiology, impaired microcirculation in patients with peripheral artery disease or diabetes mellitus and the diagnosis of inflammatory myopathies have been the subject of previous CEUS studies. More recent studies in orthopedics and traumatology have focused on osseous and muscular perfusion characteristics, e. g., in differentiating infected and aseptic non-unions or the impact of different types of implants and prostheses on muscular microcirculation as a surrogate marker of clinical success. CEUS of the musculoskeletal system is used in clinical trials or off-label. Therefore, it is not well established in clinical routine. However, considering the increasing number of musculoskeletal CEUS applications, this could change in the future.

Intrauterine growth restriction model by hyperthermia: quantitative analysis using Doppler and contrast-enhanced ultrasound imaging

Introduction: Vascular modifications mechanism in pregnancy with intrauterine growth restriction (IUGR) by placental defect is unknown. The objective of this study was to monitor and quantify uteroplacental perfusion during pregnancy in a RCIU rats model by Doppler (DUS) and contrast-enhanced ultrasound (CEUS). Materials and Methods: Thirty-six pregnant rats were randomized in three groups : control (1), hyperthermia 40&#x2103; (2), and 41&#x2103; (3). At gestational day (GD) 18 and 19, an hyperthemic stage (30 minutes) by increasing body temperature was performed for groups 2 (40&#x2103;) and 3 (41&#x2103;). DUS study was performed strictly after each hyperthermic stage. CEUS was performed on GD19 and GD20. Histological analysis of all placentas was performed after cesarian done after the last CEUS study. Weight birth of all fetuses was recorded. Results: Fetus' weight was significantly higher for group 1 compared to groups 2 and 3 (p p vs. 2 and 3 at G19 and G20. Discussion: IUGR model by hyperthermia showed a significant correlation between fetal weight birth and maternal body temperature. This IUGR is associated with a high fetal morbi-mortality with placental damage. Vascular modifications are more tissue destruction than structural modifications.

Meta-analysis of the diagnostic value of contrast-enhanced ultrasound for the detection of vascular complications after liver transplantation.

contrast-enhanced ultrasound (CEUS) is increasingly used to identify vascular complications in patients after liver transplantation. The present study aimed to evaluate the diagnostic accuracy of CEUS using all available data. relevant studies published before February 2018 were retrieved from PubMed, EMBASE, ScienceDirect and Web of Science. Pooled sensitivity and specificity, diagnostic odds ratio (DOR) and summary receiver operating characteristic curve (SROC) were calculated to estimate the diagnostic performance of CEUS for vascular complications. Sensitivity analysis was performed that stratified studies according to age, study design and sample size in order to determine the influence of these factors on the overall effect. Meta-regression analyses were performed to examine the possible sources of heterogeneity. Quality assessment and publication bias of the included studies were also evaluated. thirteen studies which consisted of 2,781 CEUS cases were included in the analysis. The pooled weighted estimates of sensitivity and specificity were 0.90 (95% CI, 0.84 to 0.95) and 1.00 (95% CI, 1.00 to 1.00), the diagnostic odds ratio (DOR) was 431.96 (95% CI, 164.60 to 1,133.59) and the area under the curve (AUC) of SROC was 0.9741. According to the sensitivity analysis, age, study design and sample size had an insignificant influence on the diagnostic performance of CEUS. The meta-regression analyses did not reveal a strong correlation between CEUS accuracy and study design, treatment time of patients and experience of the radiologists. the results of our meta-analysis showed a high sensitivity, specificity and accuracy of the CEUS modality for the identification of vascular complications in patients after liver transplantation. Since this is the first meta-analysis investigating in this aspect, more evidence is required to validate the clinical utility of CEUS for the identification of vascular complications in patients with a transplanted liver.

Early first trimester uteroplacental flow and the progressive disintegration of spiral artery plugs: new insights from contrast-enhanced ultrasound and tissue histopathology.

Does the use of a vascular contrast agent facilitate earlier detection of maternal flow to the placental intervillous space (IVS) in the first trimester of pregnancy? Microvascular filling of the IVS was demonstrated by contrast-enhanced ultrasound from 6 weeks of gestation onwards, earlier than previously believed. During placental establishment and remodeling of maternal spiral arteries, endovascular trophoblast cells invade and accumulate in the lumen of these vessels to form 'trophoblast plugs'. Prior evidence from morphological and Doppler ultrasound studies has been conflicting as to whether the spiral arteries are completely plugged, preventing maternal blood flow to the IVS until late in the first trimester. Uteroplacental flow was examined across the first trimester in human subjects given an intravenous infusion of lipid-shelled octofluoropropane microbubbles with ultrasound measurement of destruction and replenishment kinetics. We also performed a comprehensive histopathological correlation using two separately archived uteroplacental tissue collections to evaluate the degree of spiral artery plugging and evaluate remodeling of the upstream myometrial radial and arcurate arteries. Pregnant women (n = 34) were recruited in the first trimester (range: 6+3 to 13+6 weeks gestation) for contrast-enhanced ultrasound studies with destruction-replenishment analysis of signal intensity for assessment of microvascular flux rate. Histological samples from archived in situ (Boyd Collection, n = 11) and fresh first, second, and third trimester decidual and post-hysterectomy uterine specimens (n = 16) were evaluated by immunohistochemistry (using markers of epithelial, endothelial and T-cells, as well as cell adhesion and proliferation) and ultrastructural analysis. Contrast agent entry into the IVS was visualized as early as 6+3 weeks of gestation with some variability in microvascular flux rate noted in the 6-7+6 week samples. Spiral artery plug canalization was observed from 7 weeks with progressive disintegration thereafter. Of note, microvascular flux rate did not progressively increase until 13 weeks, which suggests that resistance to maternal flow in the early placenta may be mediated more proximally by myometrial radial arteries that begin remodeling at the end of the first trimester. Gestational age was determined by crown-rump length measurements obtained by transvaginal ultrasound on the day of contrast-enhanced imaging studies, which may explain the variability in the earliest gestational age samples due to the margin of error in this type of measurement. Our comprehensive in situ histological analysis, in combination with the use of an in vivo imaging modality that has the sensitivity to permit visualization of microvascular filling, has allowed us to reveal new evidence in support of increasing blood flow to the IVS from 6 weeks of gestation. Histologic review suggested the mechanism may be blood flow through capillary-sized channels that form through the loosely cohesive 'plugs' by 7 weeks gestation. However, spiral artery remodeling on its own did not appear to explain why there is significantly more blood flow at 13 weeks gestation. Histologic studies suggest it may be related to radial artery remodeling, which begins at the end of the first trimester. This project was supported by the Oregon Health and Science University Knight Cardiovascular Institute, Center for Developmental Health and the Struble Foundation. There are no competing interests.

CONTRAST-ENHANCED ULTRASOUND IMAGING OF COLORECTAL LIVER METASTASES

At present, aggressive surgical approach in combination with perioperative chemotherapy allows to extend indications for surgical intervention in patients with metastatic colorectal cancer, since only a radical liver resection provides better long-term survival. Contrast enhancement imaging techniques are important before considering treatment options to identify patients with resectable and potentially resectableliver metastases. Our study evaluated the qualitative and quantitative parameters of thedynamic enhancement pattern of liver metastases. This review will be analyzed the results of liver contrast-enhanced ultrasound studies in 104 patients with secondary colorectal liver metastases before primary tumor resection, as well as the monitoring of systemic chemotherapy and post-ablation follow-up to access treatment respond.

Imaging Features of Renal Capsule Leiomyoma on Contrast-Enhanced Ultrasonography: A Case Report

Leiomyomas of the kidney are rare, mostly occurring in adults as incidental findings, and are a diagnostic challenge. In a renal transplant recipient population, an increased risk of tumors is observed due to the effect of immunosuppressive drugs. A differential diagnosis between leiomyomas and other malignant lesions is not possible with current imaging methods. This report presents a case of a native kidney capsular leiomyoma in a kidney transplant recipient and highlights the features of computed tomography and contrast-enhanced ultrasound (CEUS), along with the histopathologic analysis. The CEUS and quantification studies are helpful in demonstrating the vascularization pattern of the renal capsular leiomyoma. This entity appearing with chronic kidney disease can resemble a renal cell carcinoma, in an otherwise healthy kidney. In this case, CEUS was useful for diagnosing the vascularization of the renal mass, although the pattern of intense vascularization could be diagnostically misleading, implying a malignant lesion. However, the pattern of enhancement due to CEUS showed no peculiarities that indicated histopathologic diagnosis.