Preoperative Contrast-enhanced Ultrasound Research Articles

Clinical cohort study of imaging evaluation and postoperative pathology of carotid vulnerable plaque

Objective: To evaluate the accuracy of contrast-enhanced ultrasound(CEUS) scanning in identifying vulnerable plaque in carotid artery. Methods: The study included a total of 25 patients who suffered from carotid artery stenosis and underwent carotid endarterectomy from January 2016 to December 2017 in Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University. Preoperative carotid artery contrast enhanced ultrasound and High-resolution MRI were performed to all patients to determine whether the plaques were stable. All patients then underwent carotid endarterectomy, during which, plaques were completely removed. Biopsies were performed using HE staining and CD31, CD34 and SMA immunohistochemistry was used to identify the plaques properties, including the thickness and integrity of the fiber cap, neovascular endothelium, hemorrhage, and inflammatory cells in the removed plaques.The results of these tests were compared with the diagnosis through the pre-operative imaging. Results: Among twenty-five cases, the pre-operative CEUS revealed sixteen with unstable plaques and nine with stable plaques. Meanwhile the post-operation pathology confirmed seventeen cases with unstable plaque components. The sensitivity of CEUS in the identification of carotid vulnerable plaque was 88.2%(15/17), the specificity was 87.5%(7/8), and the overall diagnostic accuracy was 88%(22/25). The sensitivity, specificity and overall diagnostic accuracy of high resolution MR for vulnerable plaque identification were 83.3%(10/12), 71.4%(5/7), 78.9%(15/19), respectively. There were no significant difference between two groups(χ(2)=0.003, P>0.05). Conclusions: The sensitivity, specificity and overall diagnostic accuracy of the CEUS for vulnerable plaque identification are high.Therefore, CEUS is recommended as one of the pre-operative diagnostic method for unstable plaque in carotid stenosis.

Value of Contrast-Enhanced Ultrasound in Detecting Competent and Incompetent Lower-Extremity Perforating Veins

The purpose of this study was to investigate the value of contrast-enhanced ultrasound (CEUS) in the identification of competent and incompetent lower-extremity perforating veins. Patients with chronic venous insufficiency who met the inclusion criteria were enrolled. All patients underwent pre-operative CEUS and color Doppler ultrasound (CDU) and accepted subfascial endoscopic perforator surgery. We compared the numbers of perforator veins identified by CEUS and CDU with the endoscopy result, which was considered the gold standard. Fifty cases (56 lower extremities) were enrolled. CEUS detected 132 perforating veins, and CDU detected 104 perforating veins. Endoscopy detected 148 perforating veins. The sensitivity and specificity of CDU in predicting the site of perforating veins in our study were 70.2% and 100%, respectively, and the sensitivity and specificity of CEUS were 89.2% and 100%, respectively (p < 0.05). CEUS could be used to detect perforating veins, including incompetent and competent veins of the lower extremity, because it was more sensitive than CDU, with intra-operative endoscopy as the control standard.

Preoperative Transurethral Contrast‐Enhanced Ultrasonography in the Diagnosis of Female Urethral Diverticula

To explore the value of transurethral contrast-enhanced ultrasonography (CEUS) in the diagnosis and evaluation of female urethral diverticula. This study prospectively enrolled 35 women with periurethral cystic lesions, who underwent preoperative transurethral CEUS at our single center between April 2015 and May 2017. The diagnosis of a urethral diverticulum was made by the detection of microbubbles inside the lesion. Data regarding the structure and ostia of the diverticula were collected and then compared with intraoperative findings. The median (interquartile range) age of the 35 patients was 43 (34-48) years. The most common manifestations were dysuria (43%) and palpable masses (40%). On transurethral CEUS, 20 patients were found to have urethral diverticula. The diverticula involved the proximal, mid, and distal urethra with different sizes. The shapes of the diverticula were simple in 4 patients (20%), U shaped in 8 patients (40%), and circumferential in 8 patients (40%). A total of 23 ostia were identified. Seventeen women (85%) had 1 ostium, and 3 women (15%) had 2 ostia. Twenty-one diverticular ostia (91%) were located from the 3- to 9-o'clock positions. The median (interquartile range) distance from the diverticular ostia to the bladder neck was 20 (9-31) mm. During surgery, all US presentations correlated well with surgical findings, and 21 patients were confirmed to have urethral diverticula. The transurethral CEUS had sensitivity of 95% and specificity of 100%. Transurethral CEUS is an effective method for identifying the structure and ostium of female urethral diverticula. It may have a potential role in preoperative planning and surgical management.

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.

Combined Hepatocellular Cholangiocarcinoma (Biphenotypic) Tumors: Potential Role of Contrast-Enhanced Ultrasound in Diagnosis.

The objective of this study was to evaluate the diagnostic performance of contrast-enhanced ultrasound (CEUS) in differentiating combined hepatocellular cholangiocarcinomas (CHCs) from hepatocellular carcinomas (HCCs) and intrahepatic cholangiocarcinomas (ICCs). Thirty-three patients with pathologically confirmed CHC and matched control subjects with pathologically confirmed HCC (n = 30) or ICC (n = 32) who underwent preoperative CEUS from January 2005 to December 2015 were enrolled in this study. The CEUS images of the hepatic lesions were subjectively analyzed in consensus by two radiologists. The diagnostic performances were evaluated by ROC analysis. In the arterial phase, hyperenhancement was more common in CHCs (76%) and HCCs (100%) than in ICCs (22%), whereas in the late phase marked washout was more common in CHCs (76%) and ICCs (100%) than in HCCs (10%). Using marked washout in the late phase to differentiate CHC from HCC, the area under the ROC curve (AUC) was 0.829, and the sensitivity, specificity, and accuracy were 78%, 90%, and 83%, respectively. Using hyperenhancement in the arterial phase followed by marked washout in the late phase to distinguish CHC from ICC, the AUC value was 0.663, and the sensitivity, specificity, and accuracy were 55%, 78%, and 66%. Although the imaging features of CHC, HCC, and ICC on CEUS may overlap, CEUS could be used in the differential diagnosis of CHC from HCC and ICC.

Preoperative Contrast-enhanced Ultrasonography First Diagnosed in Intravenous Leiomyomatosis

Preoperative Contrast-enhanced Ultrasonography First Diagnosed in Intravenous Leiomyomatosis

Differentiation of subtypes of renal cell carcinoma with contrast-enhanced ultrasonography.

We aimed to assess the difference of enhancement patterns among the three RCC subtypes with contrast-enhanced ultrasound (CEUS). Two hundreds cases of pathologically proved clear cell renal cell carcinomas (ccRCC), 58 papillary renal cell carcinomas (pRCC) and 51 chromophobe renal cell carcinomas (chRCC) underwent preoperative conventional ultrasound and CEUS. The wash-in and wash-out pattern, peak enhancement degree and homogeneity, and the presence of pseudocapsule were evaluated by two blinded observers respectively. The interreader agreement in the characterization of CEUS features between two observers was good (κ = 0.649-0.775). Compared with pRCCs and chRCCs, ccRCCs demonstrated higher frequency of simultaneous wash-in pattern, hyperenhancement and heterogeneity with necrotic areas. Most pRCCs and chRCCs manifested hypoenhancement, homogeneity, fast wash-out and presence of pseudocapsule. The only difference we obtained between pRCC and chRCC was the wash-in pattern, with slow wash-in in pRCC and simultaneous wash-in in chRCC. In small lesions with long diameter≤3 cm, the majority of the three subtypes of RCC showed homogeneous enhancement and there was no difference among them. CEUS was a useful method to preoperatively differentiate the ccRCC from non-ccRCC subtypes. There were no distinguishing features identifid on CEUS that allowed reliable differentiation of pRCC from chRCC.

Combined hepatocellular carcinoma and cholangiocarcinoma (biphenotypic) tumors: clinical characteristics, imaging features of contrast-enhanced ultrasound and computed tomography.

BackgroundCombined hepatocellular-cholangiocarcinoma (cHCC-CC) is an uncommon primary liver malignancy and little known about the clinical and imaging characteristics of cHCC-CC. We aim to define the demographics, imaging features of cHCC-CC on contrast-enhanced ultrasound (CEUS) and contrast-enhanced computed tomography (CT) in this study.MethodsFrom January 2005 to December 2014, 45 patients with pathologically proven cHCC-CC who underwent preoperative CEUS and 43 patients who had additional CT scan in our institution were included. A retrospective review of the imaging studies and clinical data in these patients was conducted.ResultsIn our series, cHCC-CC accounted for 1.6 % of all primary liver malignancy. Mean age of patient with cHCC-CC was 52.8 year (range: 28–74 year) and 88.9 % (40/45) of patients were male. Thirty of forty five patients (66.7 %) had cirrhosis and 20 % (9/45) of patients had chronic hepatitis B without cirrhosis. Alpha--fetoprotein (AFP) was elevated in 62.2 % (28/45) of patients and carbohydrate antigen 19–9 (CA19-9) elevated in 22.2 % (10/45) of patients). Both AFP and CA19-9 were simultaneously elevated in 15.6 % (7/45) of patients. Enhancement pattern resembling cholangiocarcinoma (CC) was noted in 53.3 % (24/45) of patients (on CEUS and in 30.2 % (13/43) of patients at CT. Enhancement pattern resembling hepatocellular carcinoma (HCC) was observed in 42.2 % (19/45) of patients on CEUS and in 58.1 % (25/43) of patients at CT. The percentage of tumors showing CC enhancement pattern (27.9 %, 12/43) was comparable with that of tumors showing HCC enhancement pattern (44.2 %, 19/43) on both CEUS and CT (p = 0.116).Simultaneous elevation of tumor markers (AFP and CA19-9) or tumor marker elevation (AFP or CA19-9) in discordance with enhancement pattern on CEUS was demonstrated in 51.1 % (23/45) of patients and on CT in 53.5 % (23/43) of patients, which was significantly more than simultaneous elevation of tumor markers (AFP and CA19-9) alone (p = 0.000).ConclusionsThe clinical characteristics of cHCC-CC are similar to those of HCC. The cHCC-CC tumors display enhancement patterns resembling CC or HCC in comparable proportion on both CEUS and CT. Combination of simultaneous elevation of tumor makers (AFP and CA19-9) and tumor mark elevation (AFP or CA19-9) in discordance with presumptive imaging findings on CEUS or CT may lead significantly more patients to be suspicious of the diagnosis of cHCC-CC.

Contrast-enhanced ultrasonography with Sonazoid for diagnosis of gangrenous cholecystitis.

This prospective study investigated the ability of contrast-enhanced ultrasonography (CEUS) with Sonazoid to diagnose gangrenous cholecystitis and determined the inter-observer agreement. From September 2012 to August 2014, 27 patients with acute cholecystitis underwent preoperative CEUS (registration number 1277). After Sonazoid injection, harmonic imaging of the gallbladder wall was performed, and the findings were recorded using movie clips. The signal intensity was classified as absence (uncomplicated) or presence of perfusion defects (gangrenous). The physician performing CEUS recorded the findings immediately after the examination. Another physician (blinded to the clinical information) then reviewed the movie clips and recorded the findings. The final diagnosis was determined by histological examination in all 27 patients. The final diagnosis was gangrenous cholecystitis in 15 patients and uncomplicated cholecystitis in 12. On CEUS examination, perfusion defects were detected in 10 patients with gangrenous cholecystitis, giving a sensitivity of 66.7 %, specificity of 100 %, positive predictive value of 100 %, and negative predictive value of 70.6 %. On review of the movie clips, these values were 73.3, 100, 100, and 75.0 %, respectively. The inter-observer agreement between physicians was good (κ coefficient, 0.64). CEUS with Sonazoid is a useful and reproducible modality for diagnosing gangrenous cholecystitis.

Quantitative Contrast-Enhanced Ultrasonic Imaging Reflects Microvascularization in Hepatocellular Carcinoma and Prognosis after Resection

Our aim was to evaluate the correlation between tumor vasculature detected by pre-surgical contrast-enhanced ultrasonography and the post-surgical prognosis of patients with hepatocellular carcinoma. One hundred ninety-five patients with hepatocellular carcinoma who had undergone curative resection and pre-operative contrast-enhanced ultrasonography were enrolled. Intra-tumoral microvessels were evaluated by immunohistochemical staining for anti-CD31 and anti-CD34. On the basis of the immunohistochemical staining and morphology patterns, tumors were divided into capillary-like and sinusoid-like microvessel subtypes. The rise time of tumors was shorter in the capillary-like microvessel subtype than in the sinusoid-like microvasculature subtype (p = 0.026). Intra-tumor microvascular density (p < 0.001, hazard ratio = 0.137) and rise time (p = 0.006, hazard ratio = 2.475) were independent factors corresponding to different microvasculature types. Microvascular density, vascular invasion and wash-in perfusion index were determined to be independent factors in recurrence-free survival and overall survival. In conclusion, contrast-enhanced ultrasonography may serve as a means of non-invasive assessment of tumor angiogenesis and may be associated with the survival of patients with hepatocellular carcinoma after resection.

Papillary renal cell carcinoma and clear cell renal cell carcinoma: Differentiation of distinct histological types with contrast – enhanced ultrasonography

PurposePapillary renal cell carcinoma (pRCC) and clear cell renal cell carcinoma (ccRCC) have different biological behaviours and imaging features. The role of contrast-enhanced ultrasound (CEUS) in differentiating these two carcinoma subtypes has not been comprehensively studied. Materials and methodsForty-eight patients with 49 pRCC lesions and 153 patients with 156 ccRCC lesions underwent preoperative conventional ultrasound (US) and CEUS. Among them, 91 patients (25 pRCCs and 66 ccRCCs) also underwent preoperative contrast-enhanced computed tomography (CECT) in our hospital. The characteristics of CEUS and CECT images for each patient imaged were analysed by each of two blinded observers. ResultsImages for five (5/25, 20%) pRCC patients demonstrated equivocal or no enhancement using CECT, while all lesions were enhanced using CEUS. From CEUS, images of pRCCs, when compared with ccRCC images, demonstrated significantly higher frequencies of slow wash-in (59.2% vs. 5.8%), fast wash-out (87.7% vs. 46.1%), and hypo-enhancement (57.1% vs. 7.1%) patterns, p<0.001, as well as the presence of pseudocapsule (42.9% vs. 23.1%), p=0.007. For lesions with large diameters (>3cm), a higher percentage of pRCC images demonstrated homogeneous enhancement compared with ccRCC images. Using the combination of slow wash-in, fast wash-out, and hypoenhancement patterns at peak as criteria to differentiate pRCC from ccRCC, positive and negative predictive value, and sensitivity and specificity were found to be 86.7%, 86.9%, 53.1%, and 97.4%, respectively. ConclusionsCEUS imaging features of slow-in, fast-out, and hypo-enhancement patterns may be useful for differentiating pRCC and ccRCC. In addition, CEUS may be helpful for diagnosing hypovascular renal lesions that demonstrate equivocal or no enhancement by CECT and, thus, for improving diagnostic confidence.

Contrast-enhanced ultrasonography to diagnose complicated acute cholecystitis.

Gangrenous cholecystitis and perforation are severe complications of acute cholecystitis, which have a challenging preoperative diagnosis. Early identification allows better surgical management. Contrast-enhanced computed tomography (ceCT) is the current diagnostic gold standard. Contrast-enhanced ultrasonography (CEUS) is a promising tool for the diagnosis of gallbladder perforation, but data from the literature concerning efficacy are sparse. The aim of the study was to evaluate CEUS findings in pathologically proven complicated cholecystitis (gangrenous, perforated gallbladder, pericholecystic abscess). A total of 8 patients submitted to preoperative CEUS, and with subsequent proven acute complicated cholecystitis at surgical inspection and pathological analysis, were retrospectively identified. The final diagnosis was gangrenous/phlegmonous cholecystitis (n. 2), phlegmonous/ulcerative changes plus pericholecystic abscess (n. 2), perforated plus pericholecystic abscess (n. 3), or perforated plus pericholecystic biliary collection (n. 1). Conventional US findings revealed irregularly thickened gallbladder walls in all 8 patients, with vaguely defined walls in 7 patients, four of whom also had striated wall thickening. CEUS revealed irregular enhancing gallbladder walls in all patients. A distinct wall defect was seen in six patients, confirmed as gangrenous/phlegmonous cholecystitis at pathology in all six, and in four as perforation at macroscopic surgical inspection. CEUS is a non-invasive easily repeatable technique that can be performed at the bedside, and is able to accurately diagnose complicated/perforated cholecystitis. Despite the limited sample size in the present case series, CEUS appears as a promising tool for the management of patients with the clinical possibility of having an acute complicated cholecystitis.

Conventional US, elastography and contrast enhanced US features of papillary thyroid microcarcinoma predict central compartment lymph node metastases

Lymph node metastases at the time of diagnosis have a major impact on both therapeutic strategy and tumor recurrence for patients with papillary thyroid microcarcinoma (PTMC). Our objective was to evaluate the usefulness of PTMC characteristics on ultrasonography for predicting central compartment lymph node metastases (CCLNM) of PTMC. One hundred twenty seven patients who underwent surgery for PTMC were enrolled in this study. The relationship between the CCLNM and the characteristics on conventional US, elastographic, and contrast enhanced ultrasound (CEUS) were investigated. Univariate analysis indicated that PTMCs with CCLNM were more often nodule irregular shape, microcalcifications, hyperenhancing or isoenhancing parametric maps, and peak index ≥1 at preoperative US and CEUS than those without CCLNM (P< 0.01, 0.05, 0.01 and 0.05 respectively). Multivariate analysis showed that microcalcification (OR:2.378, 95% CI: 1.096–5.158) and hyperenhancement or isoenhancement (OR:2.8, 95% CI: 1.287–6.094) were predictive for the presence of CCLNM. Elastography score was not significantly different between the groups. Our study indicated that preoperative thyroid nodule characteristics on conventional US and CEUS may serve as a useful tool to predict central compartment lymph node metastases in PTMC.

Contrast-enhanced sonography of thyroid nodules.

To investigate the value of contrast-enhanced ultrasound (CEUS) in the differentiation of benign and malignant nodules. One hundred eighty-nine patients with 213 thyroid nodules were enrolled in this retrospective study. All patients underwent preoperative CEUS and were subsequently scheduled for surgery. The pathology results were obtained after surgery. The time-intensity curves were plotted with TomTec software. The quantitative parameters of the time-intensity curve, such as the maximum intensity of peak (IMAX), the rise time from 10% to 90% of the IMAX, and the time to peak, were compared between the benign and malignant nodules. There were no significant differences in the rise time or the time to peak among thyroid papillary carcinoma, nodular goiter, and follicular adenoma. However, a significant difference was identified in the IMAX. A quantitative evaluation of CEUS is helpful to differentiate benign and malignant thyroid nodules.

Contrast-enhanced ultrasound (CEUS) facilitated US in detecting lateral neck lymph node metastasis of thyroid cancer patients: diagnosis value and enhancement patterns of malignant lymph nodes.

To examine the value of CEUS as a non-invasive tool in detecting lateral neck metastasis (LNM) and the enhancement patterns of malignant lymph nodes (LN) for thyroid cancer patients. Eighty-two consecutive patients, who underwent both preoperative non-enhanced US and CEUS examinations, were retrospectively reviewed. All patients underwent lateral neck dissection (LND). Enhancement patterns of 102 collected LNs matching to CEUS findings were analyzed. CEUS detected LNM in 53 of 65 patients, showing a higher sensitivity and accuracy than that of conventional US (p = 0.109 and p = 0.154, respectively). Thirteen patients' surgical procedures were altered by CEUS findings, including nine true positive and four false positive cases. Five patients' surgical procedures were altered by conventional US findings, including two true positive and three false positive cases. Heterogeneous enhancement, perfusion defects, microcalcification, and centripetal/hybrid enhancement were all specific criteria for malignant LNs in univariate analysis. In multivariate analysis, only heterogeneous enhancement and centripetal/hybrid enhancement were significantly related to LN metastasis (p = 0.000 and p = 0.037, respectively). CEUS may be a potential tool to facilitate conventional US in detecting LNM. Heterogeneous enhancement and centripetal/hybrid enhancement are useful criteria to distinguish between malignant and benign LNs. • CEUS findings facilitated conventional US in detecting LNM. • Heterogeneous, centripetal/hybrid enhancement, microcalcification and perfusion defects were specific criteria of malignant LNs. • Heterogeneous and centripetal/hybrid enhancement were significantly related to LN metastasis in multivariate analysis.

Diagnostic value of contrast-enhanced ultrasound combined with fine-needle aspiration for thyroid cancer

Objective To evaluate the diagnostic value of the contrast-enhanced ultrasound (CEUS) combined with ultrasound-guided fine needle aspiration biopsy (FNA) for thyroid carcinoma.Methods A retrospective analysis of the clinical data of 165 patients was finished,including 184 thyroid nodules confirmed by pathology (14 benign,170 malignant) and their preoperative FNA and CEUS data.According to the maximal diameter of thyroid nodules,the patients was divided into group A (≤ 1 cm) and group B (＞1 cm).According to the Bethesda System,＞grade Ⅳ was the malignant cytologic criteria for diagnosis of thyroid nodules,and uneven low-enhanced ultrasound was the standard diagnosis of malignant thyroid.Pursuant to which,the sensitivity,specificity,accuracy,positive predictive value and negative predictive value of diagnosis for thyroid nodules by FNA,CEUS,and the combination were analyzed respectively.Results In group A,the sensitivity,specificity,accuracy,positive predictive value and negative predictive value of single FNA were 93.8％,62.5％,92.0％,97.6％,38.5％,and CEUS diagnosis for thyroid cancer were 88.5％,37.5％,85.5％,95.8％,16.7％,respectively.After FNA and CEUS were combined,the sensitivity,specificity,accuracy,positive predictive value and negative predictive value were 100％,25.0％,95.7％,95.6％,100％,respectively.When the combined diagnosis compared with single FNA and CEUS,the sensitivity and accuracy were statistically significant (P =0.013,0.000 and P =0.000,0.000).In group B,the sensitivity,specificity,accuracy,positive predictive value and negative predictive value of single FNA were 100％,83.3％,97.8％,97.6％,100％,and CEUS diagnosis for thyroid cancer were 92.5％,83.3％,91.3％,97.4％,62.5％,respectively.After FNA and CEUS were combined,the sensitivity,specificity,accuracy,positive predictive value and negative predictive value were 100％,66.7％,95.6％,95.2％,100％,respectively.For each pairwise comparison,the sensitivity,specificity,accuracy,positive predictive value and negative predictive value were not statistically different (P ＞0.05).Conclusions For thyroid nodules ≤ 1cm,the combined diagnosis of FNA and CEUS can significantly improve the diagnostic sensitivity and accuracy.While for thyroid nodules ＞ 1 cm,the combined diagnosis does not change the diagnostic accuracy,sensitivity and specificity. Key words: Ultrasonography; Microbubbles ; Biopsy, needle; Thyroid neoplasms

Diagnostic value of contrast-enhanced ultrasonography in preoperative Borrmann classification of gastric cancer

To investigate the diagnostic value of contrast-enhanced ultrasonography (CEUS) in preoperative Borrmann classification of gastric cancer. Asulfur hexafluonde-filled microbubble ultrasound contrast agent and continuous real-time imaging technique of contrast pulse sequencing were used. Two hundred and eighty-five patients with gastric cancer confirmed by biopsies who received preoperative CEUS examination were involved in this study. CEUS results were compared with postoperative pathological findings. The accuracy rate of CEUS in determining the Borrmann classification of gastric cancer was 92.3%(263/285). The accuracy rates of BorrmannI(, II(, III(, IIII(, and IIIII( were 100%(12/12), 90.6%(77/85), 92.6%(126/136), 95.7%(45/47), and 60.0%(3/5) respectively. CEUS is a useful diagnostic method for preoperative Borrmann classification of gastric cancer.

Enhancement Patterns of Gastric Carcinoma on Contrast-Enhanced Ultrasonography: Relationship with Clinicopathological Features

The aim of this study was to assess the relationship between the enhancement patterns and clinicopathological features of gastric cancer using intravenous contrast-enhanced ultrasonography (CEUS). In this Ethics Committee-approved prospective study, five hundred fifty two patients with gastric cancer who gave informed consent were examined preoperatively with CEUS. The enhancement pattern of each tumor was analyzed visually. Gross and histopathological findings on the postoperative specimens were compared with the preoperative CEUS findings. The most common CEUS pattern in differentiated gastric cancer was homogeneous enhancement, whereas heterogeneous enhancement was the most common pattern in undifferentiated gastric cancer. The proportion of heterogeneous enhancement was significantly different between the two histological subtypes (Chi- square = 146.735, P<0.001). The sensitivity and specificity of early heterogeneous enhancement on CEUS in diagnosing undifferentiated gastric cancer were 78.84% and 72.59% respectively. Gastric cancers with heterogeneous enhancement were more often Borrmann III and IV macroscopic types than those with homogeneous enhancement (66.56% vs. 30.80%, P<0.001), more commonly T3 and T4 depth of invasion than those with homogeneous enhancement (71.52% vs. 59.60%, P<0.05), more often showed lymphatic invasion than those with homogeneous enhancement (84.44% vs. 76.40%, P<0.05), and were less likely to receive curative gastrectomy than those with homogeneous enhancement (74.83% vs. 86.40%, P<0.005). The intra- and inter-observer reproducibility were both almost perfect for assessing enhancement patterns, with Kappa values of 0.916 (P<0.001) for intra-observer and 0.842 (P<0.001) for inter-observer reproducibility. CEUS provided detailed information about tumor vascularity and contrast enhancement patterns in gastric cancer. CEUS is promising as a new and useful method to predict the histological type of gastric cancer.

Does Contrast-Enhanced Cervical Ultrasonography Improve Preoperative Localization Results in Patients With Sporadic Primary Hyperparathyroidism?

Objective:Pre-operative localization studies are inevitable in patients with primary hyperparathyroidism (pHPT), who are eligible for focused or minimally invasive parathyroidectomy (MIP). High-resolution ultrasonography (US) in combination with planar 99mTc-Sestamibi-scintigraphy (MIBI) and additional single-photon emission computed tomography (SPECT) are the standard procedures to localize enlarged parathyroid glands. Our aim was to evaluate the practicability and significance of contrast-enhanced ultrasonography (CEUS) in patients with pHPT.Materials and Methods:All investigations were performed at the University Hospital Marburg. Totally, 25 patients with biochemical proven pHPT underwent preoperative US, MIBI/SPECT, and CEUS. For CEUS, a suspension of phospholipid-stabilized sulfur-hexafluoride (SF6) microbubbles in combination with a special 12 MHz linear US probe was used. All patients were investigated by two sonographers, who did not get to view the findings noted by the other. Finally, surgery was performed and histopathological results were obtained from 24 patients.Results:In 17 (68%) patients, US and MIBI/SPECT already raised suspicion of parathyroid lesions and all suspected lesions were reassessed by CEUS. However, no additional information was obtained using CEUS. Especially in eight patients with negative or inconsistent US and MIBI/SPECT results, CEUS did not provide additional information regarding the site of the suspected parathyroid adenoma. Overall, no side effects were observed using CEUS. Surgical cure was achieved in all patients.Conclusion:In this limited cohort of patients, no additional information could be obtained using the costly CEUS compared to results of US and MIBI/SPECT.

Role of contrast-enhanced ultrasound for preoperative detection of colorectal liver metastases-compared with histopathologic results

Objective To evaluate the role of contrast-enhanced ultrasound (CEUS) for preoperative detection of colorectal liver metastases.Methods 42 consecutive patients with colorectal liver metastases confirmed by histopathology after surgery were recruited in the study.They all had undergone preoperative CEUS examination with contrast agent SonoVue.The number,location and size of the hepatic lesions found by CEUS were correlated with postoperatively histopathologic results on a lesion-by-lesion basis.Results 96 liver metastases in 42 patients with colorectal cancer had been resected and confirmed by histophathology.The size of the metastatic lesions ranged from 0.3～8.5 cm [average (2.6 ± 1.8)cm].From one to eight metastatic lesions were detected in one patient.21 (21.9％) metastatic lesions were equal to or less than 1.0 cm.86 of 96 metastatic lesions were correctly depicted by CEUS,with a sensitivity of 89.6％.And the sensitivity for metastatic lesions equal to or less than 1.0 cm was 71.4％ (15 of 21 tumors) by CEUS.35 metastatic lesions were found between the portal venous phase and late phase by CEUS and 19 (54.3％) metastatic lesions among them could not be detected at conventional ultrasound.The curative resection was performed in 37 (88.1％) of 42 patients.With 3 - 39 months follow-up,the intrahepatic recurrence rate within two years was 32.4％ (12 of 37 patients) and the one-year survival rate was 90.0％.Conclusions CEUS is highly sensitive for detecting liver metastases resulted from colorectal cancer,especially for small metastatic lesions.CEUS is helpful to choose reasonable therapeutic strategies and can be regarded as one of the most importantly and noninvasively preoperative imaging modalities. Key words: Ultrasonography; Microbubbles; Colorectal neoplasms; Liver neoplasms; Neoplasm metastases