Diagnostic Accuracy Of Contrast-enhanced Ultrasound Research Articles

Comparison of imaging features and diagnostic values of MRI, CT and contrast-enhanced ultrasonography in the diagnosis of cervical carcinoma staging.

This study aimed at exploring and contrasting the clinical significances and values of MRI, CT and contrast-enhanced ultrasonography in FIGO staging of cervical carcinoma. The contrast-enhanced ultrasonography, CT and MRI imaging data of 348 patients with cervical carcinoma confirmed by clinical pathology were analyzed retrospectively and contrasted with pathological findings. The total accuracy of MRI in cervical carcinoma staging was 79.89% (278/348), and the diagnostic accuracy of MRI in stage IB, stage II, stage III and stage IV of cervical carcinoma was 74.29% (26/35), 75.74% (153/202), 85.25% (52/61), 94.00% (47/50), respectively. The total accuracy of CT in cervical carcinoma staging was 73.28% (255/348), and the diagnostic accuracy of CT in stage IB, stage II, stage III and stage IV of cervical carcinoma was 60.00% (21/35), 69.80% (141/202), 78.69% (48/61), 94.00% (45/50), respectively. The total accuracy of contrast-enhanced ultrasonography in cervical carcinoma staging was 57.47% (200/348), and the diagnostic accuracy of contrast-enhanced ultrasonography in stage IB, stage II, stage III and stage IV of cervical carcinoma was 37.14% (13/35), 50.99% (103/202), 70.49% (43/61), 82.00% (41/50), respectively. The accuracy of MRI in the diagnosis of stage IB, stage II of cervical carcinoma was higher than that of CT and contrast-enhanced ultrasonography (p<0.05), and the diagnostic accuracy of CT was higher than that of contrast-enhanced ultrasonography (p<0.05). The differences among the three methods were statistically significant. According to the results of pathological sections, there were statistically significant differences among the sensitivity and specificity of MRI, CT and contrast-enhanced ultrasonography in the diagnosis of stage IB and stage II (p<0.05). MRI has high diagnostic values in the differentiation and diagnosis of cervical carcinoma staging.

Application of contrast enhanced ultrasound in TN staging of pancreas cancer: comparison with contrast enhanced computed tomography

Objective To assess value of contrast enhanced ultrasound (CEUS) in TN staging of pancreatic cancer and compared with contrast enhanced computed tomography(CECT). Methods Seventy-eight cases with pancreatic cancer confirmed by pathology were enrolled in this study. All patients were examined using CEUS and CECT and staged according to the 8th guideline of pancreas tumors of AJCC. The diagnostic accuracies of CEUS in TN staging of pancreas tumors were compared with CECT. Results The diagnostic accuracies of CEUS in T staging and N staging of pancreatic cancer were 80.8%, and 78.2%, respectively. For CECT, the diagnostic accuracies in T staging and N staging were 88.5%, and 88.5%, respectively. There was no significant difference in the diagnostic accuracies between CEUS and CECT in T staging(χ2=1.56, P=0.21). The diagnostic accuracy of CEUS in N staging was significantly lower than that of CECT(χ2=3.86, P=0.04). Conclusions The diagnostic accuracy of CEUS in T staging of pancreatic cancer is similar to that of CECT, while in its N staging is lower than that of CECT. Key words: Contrast-enhanced ultrasound; Pancreatic neoplasms; Contrast enhanced computed tomography

Vascular rejection in renal transplant: Diagnostic value of contrast-enhanced ultrasound (CEUS) compared to biopsy.

Despite of the more potent immunosuppressive medication, vascular rejection is still a major issue after renal transplantation. Renal biopsy is the gold standard diagnostic to evaluate acute and chronic allograft rejection. As it is an invasive diagnostic there is the risk of complications like haematoma, arteriovenous fistulas, active bleeding or infection. Contrast-enhanced ultrasound is a non-invasive imaging modality that allows visualising renal transplant perfusion. To analyse the sensitivity and specificity of contrast-enhanced ultrasound (CEUS) compared to biopsy as gold standard in diagnosing vascular rejection in renal transplant patients. A total of 57 renal transplant recipients with poor renal allograft function with initial diagnostic imaging between 2006 and 2017 were included in the study. Clinical data and imaging studies were analysed retrospectively. The diagnostic accuracy of CEUS in diagnosing vascular rejection of the renal transplant was compared to renal biopsy as gold standard. Out of 57 patients 7 patients showed signs of vascular rejection in biopsy. In 6 out of these 7 patients CEUS described irregularities in renal perfusion suspicious of vascular rejection. CEUS showed a sensitivity of 85.7%, a specificity of 100%, a positive predictive value (PPV) of 100%, and a negative predictive value (NPV) of 98.0%. CEUS is a safe, non-nephrotoxic imaging modality for the initial imaging of renal transplant recipients with elevated kidney function parameters suspicious of vascular rejection. Compared to renal biopsy as gold standard CEUS shows a high specificity and PPV in detecting signs of vascular rejection. Since sub-types of vascular rejection with cellular and humoral components with greater risk for allograft loss have been described renal biopsy is inevitable in these cases.

The diagnostic value of contrast-enhanced ultrasound (CEUS) as a new technique for imaging of vascular complications in renal transplants compared to standard imaging modalities.

Vascular complications in renal transplant patients are a well-known issue in post transplant patient care. If malfunctioning of the renal transplant is suspected to be caused by vascular complications an early diagnosis and therapy is required to maintain the renal transplant. Computed tomography (CT), digital substraction angiography (DSA) and radioisotope renography are the gold standard imaging modalities to diagnose vascular complications. To analyse the sensitivity and specificity of contrast-enhanced ultrasound (CEUS) in comparison to the standard imaging modalities CT, DSA and radioisotope renography in the diagnosis of vascular complications in renal transplant patients. A total of 33 renal transplant recipients with elevated kidney function parameters with initial diagnostic imaging between 2006 and 2017 were included in the study. The imaging studies and clinical data were analysed retrospectively. The diagnostic accuracy of CEUS was compared to CT, DSA and renal scintigraphy respectively which are classified as gold standard for diagnosis of vascular complications in renal transplant patients. Out of 23 patients 15 patients showed vascular complications in CT, DSA or radioisotope renography and in 15 out of 15 patients CEUS detected the vascular complication. CEUS showed a sensitivity of 100%, a specificity of 66.7%, a positive predictive value (PPV) of 71.4%, and a negative predictive value (NPV) of 100%. CEUS is a non-nephrotoxic and safe method for the initial imaging of vascular complications in renal transplant recipients. Compared to the gold standard imaging modalities CT, DSA and radioisotope renography CEUS shows a high sensitivity and NPV in detecting vascular complications. In cases with suspected stenosis of the transplant renal artery additional DSA might be needed.

Value of contrast enhanced ultrasound combined with elastography in differential diagnosis of non-mass-like lesions on breast

Objective To explore the diagnostic value of contrast enhanced ultrasound (CEUS), elastography and their combined use in diagnosing non-mass-like lesions on breast. Methods From November 2015 to January 2017, 79 nodules diagnosed by conventional ultrasound were prospectively enrolled and examined by CEUS and elastography before surgery. Multivariate logistic regression models were established for CEUS and CEUS combined with elastography to diagnose breast malignancy. The diagnostic performances of CEUS, elastography and their combined use were evaluated with the receiver operating characteristic (ROC) curve. Results The CEUS features significantly predicting malignancy were hyperenhancement, heterogeneous enhancement, visualization of penetrating vessels (P<0.01). Furthermore, the multivariate logistic regression for CEUS combined with elastography showed that heterogeneous enhancement, visualization of penetrating vessels and elasticity score were the independent predictors of breast malignancy. The area under the ROC curve of CEUS combined with elastography was (0.915±0.223), which was higher than that of CEUS and elatography (0.851±0.029, 0.790±0.038, P<0.05). Moreover, the sensitivity, and accuracy of CEUS combined with elastography were 89.1%, and 86.1%, respectively. The omission diagnostic rate of CEUS combined with elastography (8.9%) was reduced. The diagnostic accuracy of CEUS combined with elastography was significantly higher than that of CEUS and elastography. Conclusions The diagnostic value of CEUS combined with elastography was remarkably significant in the differential diagnosis of non-mass-like lesions on breast. Key words: Ultrasonography; Elasticity imaging techniques; Breast diseases/DI

Role of Contrast-Enhanced Ultrasound in the Pre-operative Diagnosis of Cervical Lymph Node Metastasis in Patients with Papillary Thyroid Carcinoma

The objective of this study was to prospectively evaluate the diagnostic accuracy of contrast-enhanced ultrasonography (CEUS) in differentiating between benign and metastatic cervical lymph nodes in patients with papillary thyroid cancer (PTC). Three hundred nineteen cervical lymph nodes (162 metastatic from PTC and 157 benign) were evaluated using conventional ultrasonography (US) and CEUS before biopsy or surgery. Metastatic lymph nodes more often manifested centripetal or asynchronous perfusion, hyper-enhancement, heterogeneous enhancement, perfusion defects and ring-enhancing margins than benign lymph nodes at pre-operative CEUS (all p values < 0.001). The area under the receiver operating characteristic curve (AUC) for the combination of conventional US and CEUS (0.983, 95% confidence interval [CI]: 0.971–0.994) was higher than that of conventional US alone (0.929, 95% CI: 0.899–0.958) and CEUS (0.911, 95% CI: 0.876–0.947). In conclusion, CEUS is a promising tool in conjunction with conventional US for the pre-operative prediction of metastatic cervical lymph nodes in patients with PTC.

Usefulness of combined use of contrast-enhanced ultrasound and TI-RADS classification for the differentiation of benign from malignant lesions of thyroid nodules

PurposeTo study the thyroid image reporting and data system (TI-RADS) classification and the contrast-enhanced ultrasound (CEUS) enhancement pattern of thyroid nodules, and to determine whether combined use of both methods is helpful in the diagnosis of thyroid nodules.MethodsA total of 319 thyroid nodules in 246 patients were assessed with TI-RADS, CEUS and a combination of both methods. The diagnostic performance of TI-RADS, CEUS and a combination of both methods was compared.ResultsThe accuracy in the diagnosis of thyroid nodules was 90.3 % for TI-RADS, 90.0 % for CEUS and 96.0 % for a combination of both methods respectively. A statistically significant difference was not observed in the diagnostic accuracy of CEUS and TI-RADS (P > 0.05). However, a significant difference was observed between a combination of both methods and either alone (P < 0.01). A combination of both methods showed high sensitivity, specificity and accuracy for TI-RADS classifications of 4a and 4b thyroid nodules compared with TI-RADS alone (P < 0.01) and a statistically significant difference was not observed for thyroid nodules classified as 2, 3, and 5 (P > 0.05).ConclusionsThe improved TI-RADS, when combined with CEUS, could significantly improve the diagnostic accuracy for thyroid nodules, especially for TI-RADS class-4 thyroid nodules.Key Points• TI-RADS can be used as the primary diagnostic standard for thyroid nodules• CEUS can be used as an important complement to TI-RADS• The improved TI-RADS can significantly improve the qualitative diagnostic accuracy

Management of incidental renal masses: Time to consider contrast-enhanced ultrasonography.

Proliferation of imaging studies for different clinical purposes and continuous improvement of imaging technology have led to an increasing number of incidental findings of renal masses. It is estimated that over 50% of patients older than 50 years have at least one renal mass. The majority of incidental renal masses are simple cysts that can be easily diagnosed by conventional ultrasonography. However, some incidental renal masses are not simple cysts, and differentiation between benign and malignant entities requires further imaging modalities. In the past, multiphase contrast-enhanced computed tomography and magnetic resonance imaging were considered the primary imaging modalities used to characterize and stage complex cystic and solid renal lesions. Currently, contrast-enhanced ultrasonography represents a novel alternative to contrast-enhanced computed tomography and magnetic resonance imaging. Contrast-enhanced ultrasonography employs microbubble contrast agents that allow the study of different enhancement phases of the kidney without risk of nephrotoxicity and radiation exposure. The diagnostic accuracy of contrast-enhanced ultrasonography in the characterization of complex renal cysts is comparable to that of computed tomography and magnetic resonance imaging, and several studies have demonstrated its reliability also in identifying solid lesions such as pseudotumors, typical angiomyolipomas, and clear cell renal carcinomas. Considering the high incidence of incidental renal masses and the need for rapid and reliable diagnosis, contrast-enhanced ultrasonography could be proposed as the first step in the diagnostic work-up of renal masses because of its safety and cost effectiveness. In this paper, we propose a diagnostic algorithm for the characterization of cystic and solid renal masses.

Value of contrast-enhanced ultrasonography in the differential diagnosis of enlarged lymph nodes: a meta-analysis of diagnostic accuracy studies.

To evaluate the diagnostic accuracy of contrast-enhanced ultrasonography (CEUS) in differentiating between benign and malignant enlarged lymph nodes using meta-analysis. Pubmed, Embase, SCI and Cochrane databases were searched for studies (up to September 1, 2014) reporting the diagnostic performance of CEUS in discriminating between benign and malignant lymph nodes. Inclusion criteria were: prospective study; histopathology as the reference standard; and sufficient data to construct 2?2 contingency tables. Methodological quality was assessed using Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2). Patient clinical characteristics, sensitivity and specificity were extracted. The summary receiver operating characteristic curve was used to examine the accuracy of CEUS. A meta-analysis was performed to evaluate the clinical utility in identification of benign and malignant lymph nodes. Sensitivity analysis was performed after omitting outliers identified in a bivariate boxplot and publication bias was assessed with Egger testing. The pooled sensitivity, specificity and AUROC were 0.92 (95%CI, 0.85-0.96), 0.91 (95%CI, 0.82-0.95) and 0.97 (95%CI, 0.95-0.98), respectively. After omitting 3 outlier studies, heterogeneity decreased. Sensitivity analysis demonstrated no disproportionate influences of individual studies. Publication bias was not significant. CEUS is a promising diagnostic modality in differentiating between benign and malignant lymph nodes and can potentially reduce unnecessary fine-needle aspiration biopsies of benign nodes.

Sa1008 Evaluation of Stiffness of the Spleen (Fibrospleen) in a Real Life Cohort of Patients With All Stages of Liver Diseases

Background and aim. Contrast enhanced ultrasound (CEUS) has improved the diagnostic work up of focal liver lesions and, according to international guidelines, is often used as the first method of choice in differentiating benign from malign lesions. However, interpretation of the contrast-enhancement patterns is a subjective modality with a certain degree of inter-observer variability. In the last years, quantitative approaches able to measure the amount and the time course of contrast uptake have shown great promise in revealing tumour response to anti-angiogenic drugs in patients with different types of malignant lesions. We evaluate the feasibility of dynamic CEUS (D-CEUS) with perfusion software as a diagnostic tool in characterizing different types of liver lesions. Patients and methods. CEUS with second generation contrast agent (Sonovue, Bracco) was performed in 22 benign and 15 malignant hepatic lesions in 32 patients 15 female and 17 male; aged 51±12 years). All cases were confirmed by MRI. Lesion vasculature was assessed in a specific harmonic mode associated with a perfusion and quantification software (Q-Lab, Philips). Five D-CEUS functional parameters (peak intensity, PI; time to PI, TP; area under the curve, AUC; slope of wash in, Pw; mean transit time, MTT) were extracted from time intensity curves and were compared among groups and applied to characterize different types of lesions. Statistical analysis was performed by a non-parametric test and a p value < 0.01 was considered statistically significant. Results. We report the preliminary results obtained in 14 hemangiomas, 8 focal nodular hyperplasias (FNH) and 20 hepatocellular carcinomas (HCC). Comparison between benign and malignant lesions revealed no statistically significant differences in all the perfusion parameters except for MTT that was longer in the first group (p = 0.005). For individual analysis, PI, AUC, and Pwi, were significantly higher in FNH than both in hemangiomas and HCC, while TTP was significantly shorter in FNH than in HCC. When we compared hemagiomas and HCC, PI, Pwi and TTP were significantly lower in the former than in the latter. Conclusion. Quantitative analysis provide a more reliable characterization of different types of liver lesions and could be an excellent tool to improve the diagnostic accuracy of CEUS. However further studies with a greater number of patients are required to confirm these results.

Contrast-enhanced ultrasonography for the diagnosis of small hepatocellular carcinoma: a meta-analysis and meta-regression analysis

The aim of this study is to determine the diagnostic accuracy of contrast-enhanced ultrasonography (CEUS) for diagnosis of small (≤ 2 cm in diameter) hepatocellular carcinoma (HCC) through a meta-analysis of published studies. A comprehensive literature search of PubMed, Embase, Web of Science, and China BioMedicine databases was conducted on articles published before 1 March 2013. Data from selected studies were pooled to yield summary sensitivity, specificity, positive and negative likelihood ratio (LR), diagnostic odds ratio (DOR), and receiver operating characteristic (SROC) curve. Statistical analyses were performed using Meta-Disc version 1.4 and STATA version 12.0 softwares. Fifteen studies were included with a total of 908 cirrhotic patients with 1,032 small hepatic nodules. All lesions were histologically confirmed through liver biopsies after CEUS. The pooled sensitivity was 0.81 (95% CI = 0.78-0.85); the pooled specificity was 0.86 (95% CI = 0.82-0.89). The pooled positive LR was 5.90 (95% CI = 3.90-8.94); the pooled negative LR was 0.20 (95% CI = 0.14-0.29). The pooled DOR was 37.07 (95% CI = 24.79-55.44). The area under the SROC curve was 0.93 (SE = 0.01). Meta-regression analysis showed that the number of lesions may be a major source of heterogeneity. No publication bias was detected in this meta-analysis. This meta-analysis indicates that CEUS is a useful diagnostic tool with high sensitivity and specificity for identifying small HCC.

Contrast-enhanced ultrasonography compared to gray-scale and power doppler in the diagnosis of peripheral lymphadenopathy

ObjectivesThe aim of the study was to evaluate the ability of contrast-enhanced ultrasonography compared to gray-scale B-mode and power Doppler in distinction between benign and malignant lymphadenopathy. MethodsIn a prospective study ultrasonography was performed in 133 patients with superficial lymphadenopathy (73 men, 60 women; mean age of 51 years, range: 18–86 years), who were examined for palpable mass in the neck, axilla or groin (104/133) and for clinical suspicion of lymphoma on the basis of positive PET/CT (29/133). 133 nodes were examined, subsequently preoperatively localized under ultrasound guidance and surgically removed; longitudinal to transverse ratio, location of nodal vessels by power Doppler and pattern of enhancement by contrast-enhanced ultrasonography with 1.5ml intravenous bolus of sulphur hexafluoride contrast agent were documented. The ultrasound findings were compared with the histology. ResultsOf all the nodes extirpated, 33 were benign, 100 were malignant (40 metastases, 60 lymphomas). Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of conventional techniques were 72%, 63.6%, 85.7%, 42.9%, 67.8% for longitudinal to transverse ratio; 73%, 60.6%, 84.9%, 42.6%, 68.3% for power Doppler versus 98.0%, 54.5%, 86.7%, 90.0%, 76.3% for contrast-enhanced ultrasonography according to Receiver Operating Characteristic analysis. ConclusionsReceiver Operating Characteristic analysis confirmed higher degree of diagnostic accuracy of contrast-enhanced ultrasonography in comparison with conventional techniques. Evaluation of nodal perfusion after intravenous administration of microbubble contrast agent can be helpful in differentiation of benign from malignant nodes.

Contrast-enhanced ultrasonography in peripheral lung consolidations: What’s its actual role?

To evaluate the diagnostic accuracy of contrast-enhanced ultrasonography (CEUS) in the differential diagnosis between neoplastic and non-neoplastic peripheral pleuro-pulmonary lesions. One hundred patients with pleural or peripheral pulmonary lesions underwent thoracic CEUS. An 8 microliters/mL solution of sulfur hexafluoride microbubbles stabilized by a phospholipid shell (SonoVue(®)) was used as US contrast agent. The clips were stored and independently reviewed by two readers, who recorded the following parameters: presence/absence of arterial enhancement, time to enhancement (TE), extent of enhancement (EE), pattern of enhancement (PE), presence/absence of wash-out, time to wash-out, and extent of wash-out. After the final diagnosis (based on histopathologic findings or follow-up of at least 15 mo) was reached, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (PLR), negative likelihood ratio (NLR) of each CEUS parameter in the differential diagnosis between neoplastic and non-neoplastic lesions were calculated. Furthermore, an arbitrary score based on the ratio between the PPVs of each CEUS parameter was calculated, to evaluate if some relationship could exist between overall CEUS behaviour and neoplastic or non-neoplastic nature of the lesions. Five patients were lost at follow-up before a conclusive diagnosis was reached, 53 lesions resulted neoplastic and 42 non-neoplastic. Enhancement in the arterial phase was observed in 53/53 neoplastic lesions and 30/42 non-neoplastic lesions. On the whole, 40/42 non-neoplastic lesions showed absence of enhancement or early enhancement (95.2%) vs 3/53 neoplastic lesions (5.7%). EE was marked in 29/53 (54.7%) neoplastic lesions and 25/30 (83.3%) non-neoplastic lesions, moderate in 24/53 (45.5%) and 5/30 (16.7%), respectively. PE was homogeneous in 6/53 (11.3%) neoplastic lesions and 18/30 (60%) non-neoplastic lesions, inhomogeneous in 47/53 (88.7%) and 12/30 (40%), respectively. 19/30 (63.3%) non-neoplastic lesions enhancing in the arterial phase had no wash-out in the venous phase, 11/30 (36.7%) had late and mild wash-out. Wash-out was early in 26/53 (49%) neoplastic lesions, late in 26/53 (49%), absent in 1 (2%); marked in 16/53 (30.2%), and moderate in 36/53 (67.9%). The delayed enhancement in the arterial phase showed a sensitivity of 94.32%, specificity of 95.2%, PPV of 96.2%, NPV of 93%, PLR of 19.81, and NLR of 0.06 in identifying the neoplastic lesions. All other parameters individually considered showed unsatisfactory values of sensitivity, or specificity, or both, in differentiating neoplastic from non-neoplastic lesions. The median of the overall arbitrary score was 3 (range 0-14) in non-neoplastic lesions, and 16.5 (range 7.0-17.5) in neoplastic lesions (P < 0.001). The correlation between the diagnosis of neoplastic vs non-neoplastic lesion and the score value was statistically significant (r = 0.858, P < 0.001). Based on the score distribution, a cut-off of 7.5 enabled to reach a sensitivity of 98.1%, specificity of 95.1%, PPV 96.3%, NPV 97.5%, PVR 20.1 and NVR 0.02 in differentiating neoplastic from non-neoplastic lesions. CEUS could be useful in the diagnostic workup of pleuropulmonary lesions. A delayed TE or a score ≥ 7.5 suggest the neoplastic nature of a lesion.

Diagnostic Accuracy of CEUS in the Differential Diagnosis of Small (≤ 20 mm) and Subcentimetric (≤ 10 mm) Focal Liver Lesions in Comparison with Histology

To evaluate the diagnostic accuracy of contrast-enhanced ultrasound (CEUS) in the differential diagnosis of small and subcentimetric liver tumors in clinical practice. 1349 patients with a hepatic tumor lacking a definite diagnosis based on B-mode ultrasound and power Doppler ultrasound were examined at 14 hospitals by CEUS using a standardized protocol (pulse/phase inversion imaging, mechanical index < 0.4). Differential diagnosis was based on the vascularity pattern and contrast enhancement pattern during the arterial, portal, and late phase according to the EFSUMB guidelines. 335 patients with focal liver lesions (FLL) ≤ 20 mm were analyzed. The tumor status established after CEUS was compared to histology (73.2 %) or in some cases to CT or MRI. A definitive diagnosis based on the gold standard was possible in 329 FLLs, while 6 FLLs remained unclear even in the combined gold standard (histology and/or CT and/or MRI). The final diagnoses of ≤ 20 mm FLL with histological confirmation (n = 241) included 87 benign and 154 malignant entities. The overall diagnostic accuracy of CEUS in FLL ≤ 20 mm with histological confirmation was 83.8 %. CEUS correctly identified 144 /154 malignant FLLs (sensitivity 93.5 %) and 58 /87 benign FLLs (specificity 66.7 %). 24 /241 FLLs remained unclear after CEUS (9.9 %). CEUS misclassified 15 /241 FLLs (6.2 %; 12 benign and 3 malignant FLLs). The positive predictive value of CEUS for a malignant FLL was 92.3 % and the negative predictive value was 95.1 %. Out of 241 small FLLs with histological confirmation, 62 FLLs were ≤ 10 mm (diagnostic accuracy of CEUS 80.6 %) and 179 FLLs were > 10 mm and ≤ 20 mm (diagnostic accuracy of CEUS 84.9 %). CEUS has a high diagnostic accuracy for the differential diagnosis of small and subcentimetric FLLs in clinical practice.

Diagnosis of colorectal hepatic metastases: Contrast‐enhanced ultrasonography versus contrast‐enhanced computed tomography versus superparamagnetic iron oxide‐enhanced magnetic resonance imaging with diffusion‐weighted imaging

To compare the diagnostic accuracy of contrast-enhanced ultrasonography (CE-US), contrast-enhanced CT (CE-CT), and superparamagnetic iron oxide-enhanced MRI (SPIO-MRI) with diffusion-weighted imaging (DWI) in the evaluation of colorectal hepatic metastases. Thirty-six patients with colorectal cancers were prospectively enrolled and retrospectively evaluated. Of the 86 metastases identified, 16 were confirmed histologically and the remaining 70 were confirmed by follow-up imaging. CE-CT and SPIO-MRI + DWI were independently evaluated by two readers, whereas CE-US was evaluated by consensus reading of two different readers. Area under receiver operating characteristic curve (A(z)), sensitivities, and positive predictive values (PPVs) were calculated and compared. For both readers, SPIO-MRI+DWI had significantly greater A(z) (0.879 and 0.904) and sensitivity (78% and 87%) for all lesions compared with CE-CT (0.779 and 0.793; 59% and 59%) and CE-US (0.811; 69%), and significantly greater A(z) (0.783 and 0.837) and sensitivity (56% and 73%) for lesions ≤1 cm compared with CE-CT (0.562 and 0.601; 20% and 22%) and CE-US (0.66; 37%). For lesions >1 cm, there was no significant difference in A(z), sensitivity and PPV between all the image sets. SPIO-MRI with DWI was the most reliable modality for evaluation of liver metastases particularly for lesions ≤1 cm.

Early diagnosis of small hepatocellular carcinoma in patients with liver cirrhosis using contrast-enhanced ultrasound and contrast-enhanced magnetic resonance

Objective To evaluate retrospectively the difference and complementary of contrastenhanced ultrasound (CEUS) and contrast-enhanced magnetic resonance (CEMR) in early diagnosis and differential diagnosis of small hepatocellular carcinoma (SHCC)(≤2.0 cm) in patients with liver cirrhosis.Methods Forty-five patients with space-occupying lesions in cirrhotic livers were included, who were referred to CEUS and CEMR before operations. Numbers as well as diagnosis results were recorded respectively,and all cases were confirmed by pathological examination. Results Seventy-five lesions were found after CEUS and CEMR,with 69 and 58 respectively. Forty-one lesions were diagnosed pathologically as SHCC by surgery or needle biopsy. Overlapping exited in enhanced mode between CEUS and CEMR.Most SHCC displayed as mode Ⅰ fast-in and fast-out and mode Ⅱ fast-in and slow-out in both examination,which can be considered as a reliable criterion. The diagnostic accuracy of CEUS and CEMR was 77. 3% (58/75) and 62. 7% (44/75) respectively (0. 50＜ P ＜0. 75). Differences of the diagnostic accuracy of SHCC with atypical enhanced mode between CEMR and CEUS were statistically significant.Conclusions There is no significant difference of diagnostic accuracy of SHCC between CEMR and CEUS.Both of these two examing procedure have its own advantages for atypical lesions, which accounts for its diagnostic difference of small SHCC and benign lesions. Key words: Ultrasonography; Microbubbles; Liver neoplasms; Liver cirrhosis; Magnetic resonance imaging

Characterisation of focal liver lesions undetermined at grey-scale US: contrast-enhanced US versus 64-row MDCT and MRI with liver-specific contrast agent

The aim of this study was to assess the role of contrast-enhanced ultrasonography (CEUS) in the characterisation of focal liver lesions in comparison with multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) with liver-specific contrast agent. One hundred and eighty-seven focal liver lesions, 91 malignant and 96 benign (mean size 3.2 cm) - proved by biopsy (n=12), histology (n=4), MDCT (n=108), MRI (n=44) MDCT/MRI (n=19) - in 159 patients were studied by CEUS. Two expert radiologists consensually evaluated the contrast-enhancement patterns at CEUS. For each lesion, they assessed: (a) nature (benign, malignant, not assessable), (b) specific diagnosis and (c) need for further radiological evaluation. Sensitivity, specificity, positive and negative predictive values and diagnostic accuracy of CEUS were calculated. A total of 167/187 (89.3%) lesions were correctly assessed as benign or malignant at CEUS, whereas 14/187 (7.5%) lesions remained undetermined and 6/187 (3.2%) were incorrectly assessed. Sensitivity, specificity, positive and negative predictive values and diagnostic accuracy of CEUS were, respectively, 89%, 89.6%, 89%, 89.6% and 89.3%. The need for further radiological evaluation decreased to 46/187 (24.6%) lesions after CEUS (p<0.001). In selected cases, CEUS can be considered an effective alternative to MDCT and MRI and reduce the need for further radiological workup.

Tumor-Specific Vascularization Pattern of Liver Metastasis, Hepatocellular Carcinoma, Hemangioma and Focal Nodular Hyperplasia in the Differential Diagnosis of 1349 Liver Lesions in Contrast-Enhanced Ultrasound (CEUS)

To evaluate the incidence and diagnostic accuracy of tumor-specific vascularization pattern in contrast-enhanced ultrasound (CEUS) in the differential diagnosis of liver tumors in clinical practice. From May 2004 to December 2006 1349 patients (male 677, female 672) with a hepatic tumor lacking a definite diagnosis based on B-mode ultrasound and power Doppler ultrasound were examined at 14 hospitals by CEUS using a standardized protocol (pulse/phase inversion imaging, mechanical index < 0.4). Vascularity pattern and contrast enhancement pattern were analyzed in focal lesions during the arterial, portal, and late phase. The tumor-specific diagnosis established after CEUS was compared to histology (> 75 % cases) or in some cases to CT or MRI. The final diagnosis of 573 benign hepatic tumors included hemangiomas (n = 242) and focal nodular hyperplasia (n = 170), other benign lesions (n = 161). Tumor-specific vascularization pattern such as a wheel-spoke pattern and arterial hyperenhancement followed by isoenhancement in the late phase in FNH or a nodular peripheral enhancement and partial or complete fill-in pattern in hemangiomas could be assessed in the majority, but not all lesions. The diagnostic accuracy of CEUS was 83.1 % for all benign lesions and 82.2 % for hemangioma and 87.1 % for FNH. The final diagnosis of 755 malignant hepatic tumors included metastases n = 383, hepatocellular carcinoma n = 279 and other malignant lesions n = 93. Late phase hypoenhancement was seen in almost all liver metastases (94.7 %) The diagnostic accuracy of CEUS was 95.8 % for all malignant lesions and 91.4 % for liver metastases and 84.9 % for hepatocellular carcinomas. Tumor-specific vascularization pattern in CEUS have a high diagnostic impact on the overall high diagnostic accuracy of CEUS for the differential diagnosis of hepatic tumors in clinical practice.

Diagnosis of small hepatic nodules detected by surveillance ultrasound in patients with cirrhosis: Comparison between contrast‐enhanced ultrasound and contrast‐enhanced helical computed tomography

To investigate the diagnostic value for the diagnosis of small (1-2 cm) hepatic nodules detected by surveillance ultrasound in patients with cirrhosis using contrast-enhanced ultrasound (CEUS) compared with that of contrast-enhanced helical computed tomography (CECT). Seventy-two liver cirrhosis patients with 103 small hepatic nodules (1-2 cm) detected by surveillance ultrasound were enrolled in the present study. All patients underwent CEUS with SonoVue as well as CECT. Nodules which appeared by contrast enhancement during the arterial phase and contrast wash-out during the late phase on CEUS or CECT were diagnosed as malignant (hepatocellular carcinoma [HCC]). Histopathology obtained from biopsy or surgery served as the gold standard. According to the above diagnostic criteria, the sensitivity (i.e. rate of correct diagnosis of HCC) was 91.1% (51/56 HCC) for CEUS and the specificity (i.e. the rate of correct exclusion of HCC) was 87.2% (41/47 regenerative nodules [RN]).Therefore, the diagnostic accuracy of CEUS was 89.3% (92/103 all nodules). Using the same diagnostic criteria, the sensitivity, specificity and accuracy of CECT were 80.4% (45/56 HCC), 97.9% (46/47 RN), and 88.4% (91/103 all nodules). Overall, there was no significant difference between CEUS and CECT in the diagnostic confidence of small hepatic nodules. Eighty-six nodules (45 HCC and 41 RN) were correctly diagnosed by both modalities and six (five HCC and one RN) were misdiagnosed by both. The ability of CEUS in the characterization of small nodules (1-2 cm) detected by surveillance US in patients with liver cirrhosis is similar to that of CECT.

2375: The role of contrast-enhanced ultrasound in pancreatic diseases characterization

Objectives: To observe the enhancement patterns of pancreatic diseases and evaluate the role of contrast-enhanced ultrasound (CEUS) in pancreatic diseases characterization compared with conventional ultrasound, contrast-enhanced CT (CECT) and biospy.Methods: Seventy-two patients with pancreatic diseases underwent CEUS using SonoVue, including 54 malignant and 18 benign cases. The time of the beginning of enhancement, peak enhancement, the beginning of wash-out and the transit time (from the beginning of enhancement to wash-out) of the diseased area and normal pancreatic tissue were analyzed for each case.Results: The beginning of enhancement of malignant pancreatic diseases was significantly slower than normal pancreatic tissue and the beginning of wash-out time was significantly faster than normal pancreatic tissue. The most common enhancement pattern of malignant diseases was peripheral enhancement with irregular nonenhanced area inside, while the benign diseases appeared homogeneous enhancement. The diagnostic accuracy of CEUS, CECT and biopsy in pancreatic diseases characterization was 87.5%, 81.8% and 92.7%, respectively, which were all significantly different from that of conventional ultrasound (56.9%). But there was no significant difference between CEUS and CECT.Conclusions: CEUS could improve the diagnostic ability in pancreatic diseases characterization. The diagnostic accuracy of CEUS is similar to CECT. Objectives: To observe the enhancement patterns of pancreatic diseases and evaluate the role of contrast-enhanced ultrasound (CEUS) in pancreatic diseases characterization compared with conventional ultrasound, contrast-enhanced CT (CECT) and biospy. Methods: Seventy-two patients with pancreatic diseases underwent CEUS using SonoVue, including 54 malignant and 18 benign cases. The time of the beginning of enhancement, peak enhancement, the beginning of wash-out and the transit time (from the beginning of enhancement to wash-out) of the diseased area and normal pancreatic tissue were analyzed for each case. Results: The beginning of enhancement of malignant pancreatic diseases was significantly slower than normal pancreatic tissue and the beginning of wash-out time was significantly faster than normal pancreatic tissue. The most common enhancement pattern of malignant diseases was peripheral enhancement with irregular nonenhanced area inside, while the benign diseases appeared homogeneous enhancement. The diagnostic accuracy of CEUS, CECT and biopsy in pancreatic diseases characterization was 87.5%, 81.8% and 92.7%, respectively, which were all significantly different from that of conventional ultrasound (56.9%). But there was no significant difference between CEUS and CECT. Conclusions: CEUS could improve the diagnostic ability in pancreatic diseases characterization. The diagnostic accuracy of CEUS is similar to CECT.