Showing papers in "Ultraschall in Der Medizin in 2011"

The EFSUMB Guidelines and Recommendations on the Clinical Practice of Contrast Enhanced Ultrasound (CEUS): Update 2011 on non-hepatic applications

Abstract: Authors F. Piscaglia1, C. Nolsøe2, C. F. Dietrich3, D. O. Cosgrove4, O. H. Gilja5, M. Bachmann Nielsen6, T. Albrecht7, L. Barozzi8, M. Bertolotto9, O. Catalano10, M. Claudon11, D. A. Clevert12, J. M. Correas13, M. D’Onofrio14, F. M. Drudi15, J. Eyding16, M. Giovannini17, M. Hocke18, A. Ignee19, E. M. Jung20, A. S. Klauser21, N. Lassau22, E. Leen23, G. Mathis24, A. Saftoiu25, G. Seidel26, P. S. Sidhu27, G. ter. Haar28, D. Timmerman29, H. P. Weskott30

Accuracy of VirtualTouch Acoustic Radiation Force Impulse (ARFI) imaging for the diagnosis of cirrhosis during liver ultrasonography.

Abstract: Purpose VirtualTouch is a new technique recently proposed to evaluate liver stiffness during B-mode ultrasonography. The goal of the present study was to analyze the diagnostic accuracy of VirtualTouch in the diagnosis of cirrhosis and its correlation with transient elastography (Fibroscan). Materials and methods A total of 133 patients with chronic liver disease were enrolled. 90 of 133 underwent VirtualTouch and transient elastography and 70 patients assessed with VirtualTouch were submitted to liver biopsy. Stiffness was assessed by both techniques in the right liver lobe. The diagnostic accuracy for cirrhosis was first assessed in the 90 patients submitted to transient elastography with > 13 kPa (47 % of patients) as diagnostic for cirrhosis values. The best cut-off for cirrhosis with VirtualTouch was then tested in the 70 patients with biopsy (cirrhosis in 38 % of patients). 41 patients were assessed by VirtualTouch by two different operators. Results The VirtualTouch values in controls, chronic hepatitis and cirrhosis were respectively 113, 147 and 255 cm/sec. The AUROC of liver VirtualTouch for the diagnosis of cirrhosis (reference Fibroscan) was 0.941 with 175 cm/sec as the best cut-off (sensitivity 93.0 %; specificity 85.1 %). VirtualTouch confirmed good performance also in patients with bioptic diagnosis of cirrhosis (AUROC 0.908, sensitivity 81.5 %, specificity 88.4 %,). The correlation of VirtualTouch with transient elastography was strict (r = 0.891) and the correlation in VirtualTouch measurements between two operators was also good (r = 0.874). Conclusion VirtualTouch is able to identify the presence of cirrhosis with good accuracy, shows good interobserver reproducibility and the correlation of its values with those obtained by transient elastography with Fibroscan is good.

Diagnostic accuracy of CEUS in the differential diagnosis of small (≤ 20 mm) and subcentimetric (≤ 10 mm) focal liver lesions in comparison with histology. Results of the DEGUM multicenter trial.

Abstract: Purpose To evaluate the diagnostic accuracy of contrast-enhanced ultrasound (CEUS) in the differential diagnosis of small and subcentimetric liver tumors in clinical practice. Materials and methods 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 Results 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 %). Conclusion CEUS has a high diagnostic accuracy for the differential diagnosis of small and subcentimetric FLLs in clinical practice.

Real-Time Elastography: Strain Ratio Measurements Are Influenced by the Position of the Reference Area.

Abstract: Purpose: Real-time elastography (RTE) is an ultrasound-based method for the visualization of relative strain distribution in soft tissues Strain ratio is a semi-quantitative measurement of strain differences between two user-defined areas in an elastogram The aim of this study was to evaluate the impact of the size and location of a reference area when measuring the strain ratio of focal lesions in a tissue-mimicking phantom and in normal liver tissue We also investigated whether the strain ratio was affected by changing the scanner parameter: elasticity dynamic range (E-dyn) Materials and Methods: Two investigators individually collected data by scanning 4 spherical inclusions with different elasticity in a phantom in which the elastic modulus was known in both the lesions and the background Subsequently, a liver scan was performed in-vivo using the same scanning protocol Five different setups with changes in reference area position or size were tested All eight levels of the scanner setting Edyn were recorded for each setup and the strain ratio was measured in 3 different representative elastograms for each recording situation Results: The four inclusions had significantly different mean strain ratio levels (p Conclusion: Strain ratio provides reproducible measurements of inclusions representing different elastic contrasts using a free-hand technique in vitro Changes in the distance of the reference areas to the ultrasound probe, representing the stress source, seem to have a significant impact on strain ratio measurements

Thyroid stiffness assessment by acoustic radiation force impulse elastography (ARFI).

Abstract: PURPOSE: To evaluate and compare the values of thyroid tissue elasticity in subjects without known thyroid pathology, in patients with Graves’ disease and with chronic autoimmune thyroiditis (CAT). PATIENTS AND METHODS: We performed a prospective study that included 74 subjects, 23 without thyroid pathology, 29 with Graves’ disease and 22 with CAT (diagnosed by specific tests). In all patients, 10 elastographic measurements were performed in the right thyroid lobe (RTL) and 10 in the left thyroid lobe (LTL) using a 2 – 6 MHz convex probe. Median values were calculated for each thyroid lobe, measured in meters/second (m/sec). We calculated a mean ARFI value from measurements made in the RTL and LTL. RESULTS: Thyroid stiffness was statistically significant lower in normal subjects vs. those with Graves’ disease (2.07 ± 0.44 m/sec vs. 2.82 ± 0.47 m/sec, p < 0.001) and with CAT (2.07 ± 0.44 m/sec vs. 2.49 ± 0.48 m/sec, p = 0.004). We also found a statistically significant difference between subjects without thyroid pathology and those with autoimmune thyroid pathology (Graves’ disease and CAT) (2.07 ± 0.44 m/sec vs. 2.68 ± 0.50 m/sec, p < 0.001). CONCLUSION: ARFI seems to be a useful method for the evaluation of diffuse thyroid gland pathology and is able to predict with sufficient accuracy the presence of thyroid diffuse diseases (AUROC = 0.80).

Significant differentiation of focal breast lesions: raw data-based calculation of strain ratio.

Abstract: PURPOSE We compared elastography, B-mode ultrasound and mammography to determine whether raw data calculation of strain ratios (SRs) can further improve the differentiation of focal breast lesions. MATERIALS AND METHODS 201 women with histologically proven focal breast lesions (85 benign, 116 malignant) were included at two German breast centers. Patients underwent a standardized ultrasound procedure using high-end ultrasound system with a 9-MHz broadband linear transducer. Two experienced readers analyzed the B-mode scans and mammograms using the BI-RADS criteria, while elastograms were analyzed using the Tsukuba score. SRs were calculated from a tumor-adjusted ROI and a comparable ROI placed in the lateral fatty tissue. The sensitivity, specificity, and cutoff values were calculated for SRs (ROC analysis). RESULTS The median age was 53 years. The sensitivity and specificity were 85 %/ 60 % for B-mode scanning, 85 %/ 68 % for elastography, 78 %/ 62 % for mammography, and 95 %/ 74 % for SRs. An SR cutoff value of 2.27 (AUC 0.907) allowed significant differentiation (p < 0.001) between malignant and benign lesions. The quantitative SR calculation was superior to subjective interpretation of B-mode scans and sonoelastograms with a positive predictive value of 83 % versus 78 % and 74 %, and equal to mammograms. CONCLUSION Strain ratio calculation contributes to the standardization of sonoelastography with high sensitivity and allows significant differentiation between benign and malignant breast lesions with a higher specificity compared to B-mode, subjective evaluation of elastography and mammography.

Frequency of tumor entities among liver tumors of unclear etiology initially detected by sonography in the noncirrhotic or cirrhotic livers of 1349 patients. Results of the DEGUM multicenter study.

Abstract: Ziel: Untersuchung der Haufigkeit von verschiedenen soliden fokalen Leberlasionen (SFLL) in nicht zirrhotischen und zirrhotischen Lebern unter besonderer Berucksichtigung der Haufigkeit der Metastasierung in Zirrhoselebern. Material und Methoden: Das Patientenkollektiv der DEGUM-Multicenterstudie (n = 1349) wurde reevaluiert und in ein Subkollektiv A ohne (n = 1067) und B mit Zirrhose (n = 282) unterteilt. Die verschiedenen Tumorentitaten waren zu 74,6 % histologisch gesichert (n = 1006). Ergebnisse: Im Subkollektiv A fanden sich 385 Falle mit Metastasen (36,4 %) und 65 mit HCC (6,1 %), demgegenuber waren an benignen Lasionen Hamangiome mit 237 Fallen (22,4 %) und FNH mit 170 Fallen (16,1 %) am haufigsten. Im Subkollektiv B fanden sich 216 Falle von HCC (76,6 %) und 12 Metastasen (4,3 %), sowie 42 benigne Lasionen (14,9 %). CCC waren im Subkollektiv A (3,3 %) und im Subkollektiv B (2,5 %) selten. Eine Tumoranamnese erhoht die Wahrscheinlichkeit fur eine maligne SFLL im Subkollektiv A 1,8-fach, nicht jedoch im Subkollektiv B. Schlussfolgerung: Die Haufigkeit der verschieden Tumorentitaten unterscheidet sich bei Patienten mit und ohne Zirrhose grundlegend. In nicht zirrhotischen Lebern sind maligne und benigne SFLL etwa gleich haufig. Im Vordergrund stehen Metastasen, Hamangiome und FNH, CCC sind selten. Eine Tumorvorgeschichte erhoht die Wahrscheinlichkeit auf eine maligne SFLL. Bei Zirrhose dominieren HCC, HCC sind 18-mal haufiger als Metastasen. Benigne SFLL und CCC sind selten

Characterization by Biopsy or CEUS of Liver Lesions Guided by Image Fusion between Ultrasonography and CT, PET/CT or MRI

Abstract: PURPOSE: The aim of this study was to show the number of cases in which the use of fusion-guided ultrasonography (US) provided conclusive diagnosis of lesions in the liver seen on CT or MRI or PET/CT. A lesion is defined as a region that has suffered damage due to injury or disease. MATERIALS AND METHODS: Forty patients of whom 34 had confirmed neoplastic disease, referred to US evaluation or US-guided biopsy of liver lesions seen on CT (n = 35), MRI (n = 2) or PET/CT (n = 3), were prospectively included in the study. We used a LOGIQ prototype system with incorporated software for fusion imaging, and a convex-array 4 MHz transducer (GE Healthcare, Chalfont St. Giles, UK). All patients were initially examined with B-mode US, then by fusion-guided US and for some patients also with CEUS. All patients received follow-up after at least one year. RESULTS: Twenty-six lesions were initially indistinguishable with US. Of these, 9 became visible with fusion-guided US and another 4 became visible with CEUS, which facilitated a final diagnosis in 11 of these 13 patients. The median tumor size for all lesions included in the study was 1.5 cm (interquartile range: 1.0 - 2.4). There was no statistically significant difference in tumor size between the groups. CONCLUSION: We have successfully demonstrated an increase in the characterization of liver lesions by using fusion-guided US compared with conventional B-mode US.

Efficacy of contrast-enhanced US versus CT or MRI for the therapeutic control of percutaneous radiofrequency ablation in the case of hepatic malignancies.

Abstract: PURPOSE: The goal of this study was to assess the informative value of contrast-enhanced ultrasound after radiofrequency ablation (RFA) Patients who had undergone RFA of malignant liver tumors were followed up with contrast-enhanced sonography (CEUS), computed tomography (CT) and/or magnetic resonance tomography (MRI), and the outcomes were compared MATERIALS AND METHODS: 76 patients undergoing 194 RFAs for 118 hepatic neoplasms (n = 55 HCC, n = 63 metastases) in the course of a 7-year period were examined post-interventionally using CEUS and CT or MRI During follow-up (gold standard of evaluation), contrast agent rim accumulations with a diameter greater than 5 mm and a growth rate of at least 25 % were counted as a recurrence RESULTS: CEUS-CT comparison group: A total of 65 scan pairs were compared In 54 cases (831 %) the findings were the same with either method In 7 cases (108 %) CEUS confirmed the correct diagnosis, and in 2 cases (31 %) only CT was correct In 2 cases (31 %) both methods yielded incorrect results Diagnostic accuracy (DA): CEUS 938 %, CT 862 % CEUS-MRI comparison group: In 23 cases (885 %) of a total of 26 scan pairs, the findings were the same for both CEUS and MRI In 3 discordant cases only CEUS confirmed the correct diagnosis (3 cases, 115 %) Diagnostic accuracy DA (n = 26): CEUS 100 %, MRI 884 % CONCLUSION: CEUS performs equally to CT and MRI in the follow-up of patients treated for liver tumors by RFA

Individualized correction for maternal weight in calculating the risk of chromosomal abnormalities with first-trimester screening data.

Abstract: Aim In the algorithm developed by the Fetal Medicine Foundation (FMF) Germany designed to evaluate the findings of routine first-trimester screening, the false-positive rate (FPR) was determined for the entire study group without stratification by maternal weight. Based on the data received from the continuous audit we were able to identify an increase in the FPR for the weight-related subgroups of patients, particularly for patients with extremely high body weights. The aim of this study was to demonstrate that the variability of the FPR can be reduced through adjusting the concentrations of free β-HCG and PAPP-A measured in the maternal serum by means of a nonlinear regression function modeling the dependence of these values on maternal weight. Material and methods The database used to establish a version of the algorithm enabling control of the FPR over the whole range of maternal weight consisted of n = 123 546 pregnancies resulting in the birth of a child without chromosomal anomalies. The group with positive outcomes covered n = 500 cases of trisomy 21 and n = 159 trisomies 13 or 18. The dependency of the serum parameters free β-HCG and PAPP-A on maternal weight was analyzed in the sample of negative outcomes by means of nonlinear regression. The fitted regression curve was of exponential form with negative slope. Using this model, all individual measurements were corrected through multiplication with a factor obtained as the ratio of the concentration level predicted by the model to belong to the average maternal body weight of 68.2 kg, over the ordinate of that point on the regression curve which belongs to the weight actually measured. Subsequently, the totality of all values of free β-HCG and PAPP-A corrected for deviation from average weight were used as input data for carrying out the construction of diagnostic discrimination rules described in our recent paper for a database to which no corrections for over- or under-weight had been applied. This entailed in particular the construction of new reference bands for the corrected biochemical values as the basis for calculating the degree of extremeness (DOE) measures to replace the more traditional MOMs. In the final and most crucial step, stratified FPRs were computed and compared over a set of intervals partitioning the whole range of maternal weight into 18 classes. Results For the posterior risks of both trisomy 21 and 13 / 18 computed from the weight-corrected database, the use of a cutoff value of 1:150 turned out to be an appropriate choice. For T 21, the overall FPR obtained through comparing the individual risks with this cutoff was found to be 3.51 %. The corresponding proportion of ascertained cases of trisomy 21 detected by means of the new algorithm was 86.2 %. For the trisomy 13 / 18 group, the analogous results were a FPR of 2.07 % and a detection rate (DTR) of 83.0 %, respectively. A comparison between the FPRs obtained for the 18 intervals into which the range of maternal weight had been partitioned, showed the deviation of the strata-specific from the overall FPR to be fairly small: for T 21, the FPR ranged from 2.72 to 4.86 %, and the maximum was found in the group of 87.5 - 95.0 kg. For women with a weight of more than 120 kg, the FPR was only slightly above the FPR for the total sample (3.69 as compared to 3.51 %). Similar results were obtained for the discrimination rule constructed for diagnosing T 13 / 18: here, the minimum FPR (1.17 %) was found for patients weighing more than 120 kg, whereas the maximum (2.66 %) occurred in the interval 75.0 - 77.5 kg. Conclusion In this study we demonstrated that the new algorithm developed by the FMF Germany to estimate risks for fetal trisomies 21 and 13 / 18 combines very good misclassification rates with a far-reaching stability of the false-positive rate against even extreme deviations from the average maternal weight.

Microwave ablation of liver metastases guided by contrast-enhanced ultrasound: experience with 125 metastases in 39 patients.

Abstract: Purpose The aim of our study was to evaluate the efficacy of microwave (MW) ablation of liver metastases guided by B-mode ultrasound (US) and contrast-enhanced US (CEUS). Materials and methods 39 patients (17 women and 22 men) with a total of 125 liver metastases were treated with percutaneous or intraoperative CEUS-guided MW ablation. The primary tumor was colorectal cancer (n = 31), breast cancer (n = 6), carcinoid tumor (n = 1), and gastrointestinal stromal tumor (GIST) (n = 1). The median number of metastases ablated in the 45 treatment sessions was 2 (range 1 - 11). The median size (maximum diameter) of the 125 metastases was 1.5 cm (range, 0.6 - 4.0 cm). Nineteen (15 %) of the 125 metastases were bigger than 2 cm. Metastases smaller than 2 cm were treated with a single needle, metastases bigger than 2 cm were treated with 2 or 3 parallel needles. Results The 45 MW ablation sessions were performed percutaneously (n = 30), during laparotomy (n = 3), or during laparotomy combined with liver resection (n = 12). The 39 patients were followed up for at least 4 months with a median duration of 11 months (range, 4 - 20 months). The technical success rate was 100 %. The clinical effectiveness was 100 % with complete coverage of the metastasis by the avascular coagulation zone evaluated on immediate post-ablation CEUS. Local tumor progression (local recurrence) was seen in 12 (9.6 %) of the 125 treated metastases, and affected 10 (26 %) of the 39 patients. One major complication was observed in the form of a liver abscess that easily resolved after percutaneous drainage. Four minor complications were observed: Three cases of pain located at the puncture site and one case of ascites. CEUS was valuable in all phases of ablation including pre-ablation staging and procedure planning, placement of MW needles in the tumor, immediate post-ablation control of coagulation size, and finally in the long term follow-up regime. Conclusion CEUS-guided MW ablation of liver metastases is an efficient and safe ablation technique with several advantages compared to other ablation modalities.

Evaluation of an OSCE assessment tool for abdominal ultrasound courses.

Abstract: Purpose The purpose of this study was the conception and evaluation of a standardized and reliable assessment tool in the OSCE format to measure the performance and practical skills of abdominal ultrasound users in PGME. Materials and methods The design, logistics, pacing and the choice of tested competencies of a rotating OSCE parcours, as well as the options for quality control using detailed checklists versus global rating scales and different approaches to the training of the involved raters are described. Over the last 15 years the parcours has undergone incremental improvement and has been used in final examinations of abdominal ultrasound courses with approximately 5000 medical students and 2000 residents and fellows. For evaluation, all item difficulties and discrimination coefficients of the individual stations and the reliability (Cronbach's alpha) were calculated for the last 626 assessments. Results All 14 hands-on stations showed discrimination coefficients from 0.31 to 0.65 (mean 0.48; SD 0.09). The 13 diagram stations showed mean values of 0.50 (SD 0.16). Data analysis revealed mean homogeneous item difficulties of 0.78 (SD 0.02) and 0.62 (SD 0.04), respectively. Cronbach's alpha was 0.69 with five stations and reached values above 0.8 when more than 8 stations are combined in one parcours. Conclusion The homogeneous distribution of item difficulties provides an opportunity for designing different OSCE versions with different levels of reliability. Several options to adjust the cut-off values, the choice of the examined contents and factors that influence the examinees' acceptance of this assessment tool for PGME or CME ultrasound courses are discussed. Overall, the values of reliability and accuracy of this assessment tool are high enough to be used also for high-stakes examinations in the field of abdominal ultrasound.

Differentiation between benign and malignant adrenal mass using contrast-enhanced ultrasound

Abstract: Purpose Adrenal masses can be detected by ultrasound with high sensitivity and specificity. The aim of the present study was to evaluate CEUS in a large patient population using CEUS patterns identified in a previous pilot study. Materials and methods 116 adrenal masses were evaluated by ultrasound, including CEUS with the contrast agent Sonovue®. The dynamic of contrast enhancement (CE) was analyzed using time-intensity curves. The time of the first CE in the adrenal mass was used to define four CEUS patterns: pattern I = early arterial CE, pattern II = arterial CE, pattern III = late CE, pattern IV = no CE. In addition, all patients received CT/MRI and hormonal testing. In suspicious cases biopsy or adrenalectomy was performed. Results CEUS patterns II100]) and 67 % (CI [56;75]), respectively. Overall histology was available as a reference method for 40 adrenal masses. In 68 % of histologically diagnosed adrenal masses, MRI/CT and CEUS were congruent concerning the characterization of malignant versus benign adrenal mass. Conclusion Contrast-enhanced ultrasound may be a useful method in the diagnostic work-up of adrenal mass with excellent sensitivity for the diagnosis of malignancy.

Measurement of the Optic Nerve Sheath Diameter in Children: Comparison Between Transbulbar Sonography and Magnetic Resonance Imaging.

Abstract: Purpose: To evaluate the accuracy of measurements of the optic nerve sheath diameter (ONSD) in children by comparing transbulbar sonography with magnetic resonance imaging (MRI). Materials and Methods: 65 children (age: 3 mo– 17y; mean age: 11.3y) underwent MR imaging of the brain including a heavily T 2-w sequence of the orbit and transbulbar sonography using a 17 MHz linear array transducer. Measurements of the ONSD were performed retrospectively by two experienced readers and all images were evaluated regarding the image quality. Bland-Altman Plots were produced to assess the accuracy of measurements. The correlation between readers and between MR imaging and transbulbar sonography was calculated by the concordance correlation coefficient (CCC). Results: Overall the mean values of the ONSD for MRI (5.86 ± 0.66 mm) and transbulbar sonography (5.86 ± 0.71 mm) were identical. There was a high correlation between readers for measurements of the ONSD both for transbulbar sonography (CCC = 0.93) as well as for MRI (CCC = 0.9). Comparing the measurement values between transbulbar sonography and MRI, the correlation of ONSD values was good to moderate with a high dependency on image quality (CCC [0.31, 0.68]). Conclusion: We were able to demonstrate that the ONSD values of transbulbar sonography in children correlate well with MRI if the relevant anatomic structures are depicted and the measuring points are set correctly. Based on the findings of our study, it seems necessary to define normal and cut-off values for the ONSD in children again to finally assess the clinical relevance of the ONSD as a noninvasive parameter for the evaluation of intracranial pressure.

Interventional ultrasound-guided procedures in pancreatic pseudocysts, abscesses and infected necroses - treatment algorithm in a large single-center study.

Abstract: UNLABELLED Through a time period of 5 years, all consecutive patients were documented in this prospective single centre observational clinical study to investigate feasibility and outcome of ultrasound(US)- and EUS-guided drainage of symptomatic non-infected pancreatic pseudocysts and abscesses as well as the endoscopic debridement of infected necroses. RESULTS From 03 / 23 / 2002 to 12 / 31 / 2008, 147 patients (females:males = 49:98 [1:2.0]) with pseudocysts (n = 32), abscesses (n = 81) and necroses (n = 34) were enrolled in the study. Technical success rate in US-guided external and in EUS-guided transmural drainage was 100 % and 97.0 %, respectively, whereas that of transpapillary (ERP-guided) drainage was 92.1 %. While the complication rate in external drainage was 3.7 %, this rate in transmural and transpapillary drainage was 9.6 % and 0, respectively. Late complications (> 24 h) were observed in 6.4 % of patients after transpapillary drainage (external drainage, 5.6 %; transmural drainage, 19.1 %). Complications in 5 cases (bleeding, n = 3; perforation, n = 1; dislocation of the prosthesis with perforation of the terminal ileum, n = 1) needed to be approached surgically. After a mean follow-up period of 20.7 months, 20.9 months, and 19.4 months, the definitive therapeutic success rate was 96.2 % in average for the three diagnoses such as pseudocyst (96.9 %), abscess (97.5 %), and necrosis (94.1 %), respectively (recurrency rate, 15.4 % in average; overall mortality, 0.7 % but no intervention-related death). CONCLUSION US- and endoscopy-based management of pancreatic lesions as reported is suitable and favorable also in daily clinical routine since it is a safe and efficacious approach in experienced hands.

Diagnostic sonography of peripheral nerves: indications, examination techniques and pathological findings.

Abstract: 1. Erlernen der wichtigsten Indikationen zur Sonografie peripherer Nerven. 2. Erlernen der wesentlichen technischen Vorraussetzungen, der Gerateeinstellungen und deren Optimierung zur hochauflosenden Weichteil(WT)-Sonografie sowie der sonografischen Untersuchungstechnik. 3. Erlernen der sonografischen Anatomie der mit Ultraschall (US) darstellbaren peripheren Nerven. 4. Erlernen der sonografischen Pathologie von peripheren Nerven (Kompressionssyndrome an der oberen und unteren Extremitat, posttraumatische und postoperative Veranderungen, periphere Nerventumoren).

New technology - demonstration of a vector velocity technique.

Abstract: With conventional Doppler ultrasound it is not possible to estimate direction and velocity of blood flow, when the angle of insonation exceeds 60-70°. Transverse oscillation is an angle independent vector velocity technique which is now implemented on a conventional ultrasound scanner. In this paper a few of the possibilities with transverse oscillation are demonstrated.

[Contrast-enhancend sonography (CEUS) in pneumonia: typical patterns and clinical value - a retrospective study on n = 50 patients].

Abstract: PURPOSE To describe contrast-enhanced ultrasound (CEUS) patterns of pneumonia, to characterize CEUS patterns and to determine the clinical value of deviant CEUS patterns. PATIENTS AND METHODS N = 50 patients with radiologically diagnosed alveolar pneumonia were investigated by CEUS and retrospectively evaluated. Pulmonary enhancement was differentiated from bronchial arterial enhancement by measurement of time to enhancement from the application of the contrast agent (CA). The echogenicity of the CA enhancement was evaluated (isoechoic/hypoechoic) using the spleen as an "in vivo reference". In addition, the homogeneity of the CA enhancement (homogeneous/ inhomogeneous) was recorded. The patients were divided into two groups according to the CEUS pattern (type 1/type 2) and compared to each other in terms of age, days of hospitalization, comorbidity, rate of complications and the presence of pleural effusion. RESULTS The majority showed a type 1 CEUS pattern consisting of a pulmonary arterial supply (92 %), an isoechoic extent of enhancement (74 %) and a homogeneous enhancement (78 %) of the CA in the pulmonary lesions. The only significant difference found between the two groups was the average age. CONCLUSION Pneumonia most likely shows a type 1 CEUS pattern consisting of a pulmonary arterial supply, an isoechoic extent of enhancement compared to the spleen and a homogeneous enhancement of the CA in the pulmonary lesions. Prognostic value of a type 2 CEUS pattern (bronchial arterial supply and/or hypoechoic extent of enhancement and/or inhomogeneous enhancement) in pneumonia regarding days of hospitalization, comorbidity, rate of complications and the presence of pleural effusion could not be shown.

Diagnostic value of quantitative EUS elastography for malignant pancreatic tumors: relationship with pancreatic fibrosis.

Abstract: PURPOSE EUS elastography has been used to facilitate the diagnosis of pancreatic cancer, but as yet the interpretation of this procedure has been largely subjective. The present study has been designed to validate a quantitative approach for the analysis of EUS elastography, and to assess its relationship with pancreatic fibrosis. MATERIALS AND METHODS 86 patients with malignant pancreatic masses and 28 control subjects without any evidence of pancreatic diseases were examined by EUS elastography. EUS video sequences were subjected to a quantitative analysis based on mean hue histogram analysis. Pancreatic fibrosis was determined by quantitative morphometry in tissue specimens from 36 patients. RESULTS The mean RGB (red, green, blue) value was significantly higher in the cancer patients compared to the controls (14.0 ± 0.4 vs. 11.5 ± 0.9; p = 0.0085), albeit with significant overlap between the groups. In contrast, a much sharper separation between the groups was obtained based on the individual color values for blue, green and red (p < 0.0001, respectively). By these means, 100 % sensitivity and specificity for the distinction between tumor and normal tissue was obtained for the blue color value, while the red and green color values were less discriminative. The fractional fiber content of the tumors was unrelated to the respective hue histogram color values. CONCLUSION Quantitative EUS elastography allows for clear differentiation between malignant pancreatic tumors and normal tissue. Using this approach, we demonstrated that the stiffness of pancreatic tumors is largely independent of their fiber content.

ARFI elastography of the spleen is inferior to liver elastography for the detection of portal hypertension.

Abstract: PURPOSE To date, the use of transient elastography has been limited to the liver. Acoustic radiation force impulse imaging (ARFI) is a new technology offering elastography of different tissues. Here, we present initial spleen elastography data and evaluate its influencing factors, especially portal hypertension. MATERIALS AND METHODS Elastography of the spleen and liver using the ARFI method was performed in 30 patients with portal hypertension, 70 patients with chronic liver disease without portal hypertension and 25 healthy controls. RESULTS ARFI elastography of the spleen was feasible in 99% of patients and valid in 78%. The mean propagation velocity inside the spleen was 2.95 ± 0.60 m/sec, thus much higher than in the normal liver (< 1.10 m/sec). Spleen stiffness was higher in the patients with portal hypertension (p < 0.008) but did not correlate to spleen size. Spleen stiffness increased with patient age and liver stiffness (both p < 0.0001) as confirmed by multivariate analysis (R2 = 0.19, p < 0.01). In ROC analysis, spleen elastography was inferior to liver elastography for the detection of portal hypertension (area under the curve 0.68 vs. 0.90). CONCLUSION The new ARFI method allows accurate elastography of the spleen. The stiffness of the normal spleen is much higher than that of the normal liver and increases with age. However, spleen elastography is inferior to liver elastography for the detection of portal hypertension.

Fetal aberrant right subclavian artery (ARSA) - a potential new soft marker in the genetic scan?

Abstract: Purpose The aim of this study was to evaluate the prevalence of an aberrant right subclavian artery (ARSA) in a mixed-risk population in the second trimester and to assess its potential as a new soft marker in the genetic scan. Materials and methods Fetal echocardiography was performed prospectively in 1337 fetuses at 16 - 28 weeks of gestation during a 12-month period at two referral centers for prenatal diagnosis. The presence of ARSA was verified by visualization of the transverse 3-vessel trachea view with color Doppler sonography. Results The total rate of fetuses with an ARSA was 1.05 % (14 / 1337). The spectrum of associated findings in affected fetuses included: one trisomy 21, one unbalanced inversion of chromosome 9, one triploidy and two non-chromosomally related structural defects. Nine fetuses had no anomalies. The calculated odds ratio for the presence of an ARSA in the case of Down syndrome compared with healthy fetuses was 12.6 (95 % CI, 1.93 - 86.10). Conclusion The presence of an ARSA is more common in fetuses with trisomy 21 and other chromosomal defects than in healthy fetuses. Although it can be considered as a weak marker, the second trimester diagnosis of an ARSA should prompt a detailed search for additional "soft markers" and structural defects.

Primum non nocere? Why can't we use second generation ultrasound contrast agents for the examination of children?

Abstract: The first ultrasound examinations were performed at times when physical bases of CT (computed tomography) and MRI (magnetic resonance imaging) were formed. However, the first ultrasound contrast agents (UCAs), Echovist® and Albunex®, were registered for diagnostic purposes as late as the mid-1980 s [1], although the contrast media had long been used for CT and MRI on a routine basis at that time. The history of UCAs starts with the end of the 1960 s, with the first attempts to visualize the aorta using a solution of physiological saline with multiple air bubbles [2]. The next stage was the registration of UCAs: Echovist® and Albunex®, which allowed for their echocardiographic application. At the beginning of the 1990 s, the first publications on Levovist® appeared. This preparation turned out to be useful not only in heart diagnostics, but also in the evaluation of focal lesions in the spleen and liver. In pediatric diagnostics, it was fully accepted for the purposes of assessing vesicoureteral reflux. Levovist® was finally registered in 1996. After the year 2000, second-generation UCAs were launched on the market: Imagent®, Definity® (USA/Canada)/LuminityTM (EU), OptisonTM, SonoVue®. The first contrast agent is registered in the United States only. Remaining agents Definity® (under the name of: LuminityTM), OptisonTM and SonoVue® were registered in Europe. Apart from the SonoVue® contrast agent, the registration indications of all remaining second-generation UCAs include echocardiographic purposes only. In the registration document for the SonoVue® contrast agent, marketed in the EU in the year 2001, there are also other applications mentioned, apart from echocardiography. These include the assessment of microflows and large vessel flows. In the first years after the introduction of SonoVue®, most of the publications focused on its potential for the detection and characterization of focal liver lesions. The results of these studies, showing a similar or even a higher sensitivity and specificity than CT or MRI, changed the diagnostic algorithms and marked a breakthrough in ultrasonography owing to second-generation UCAs. The initial guidelines concerning clinical application of UCAs were developed in 2004 by a group of experts – EFSUMB (European Federation of Societies for Ultrasound in Medicine and Biology). There were eight pages with information on the registered second-generation UCAs and recommendations concerning their application in the detection and interpretation of hepatic focal lesions, as well as the evaluation of thermoablation procedures of hepatic tumors [3]. In 2008, the reedited version of the guidelines had 17 pages and included new recommendations regarding the application of UCAs: evaluation of focal lesions within kidneys, evaluation of the transplanted kidney, lesions within the pancreas, patients after blunt traumas of the abdominal cavity and transcranial ultrasonography [4]. Since 2008, there have been new articles in the literature, concerning the usefulness of the SonoVue® contrast agent for the diagnostics of muscle trauma, the degree of activity of the Crohn’s disease process, the differentiation of the focal lesions within breasts, the location of the focal lesions within adrenal glands, the evaluation of the lesions within the parotid glands, and others [5–9]. It should be emphasized that none of the UCAs (neither first nor second-generation) are registered for individuals under 18 years of age. It is therefore interesting that according to guidelines regarding the clinical application of ultrasound contrast agents developed by the EFSUMB group of experts in 2008, UCAs (except Levovist®) cannot be used for diagnosing vesicoureteral reflux in children. However, this diagnostic method is presented during UCA training sessions organized by EFSUMB (Hanover – 2008). Despite the fact that UCAs are not registered for individuals under 18, SonoVue is applied in the pediatric population in some European centers. There are also publications concerning the advantages of UCA application in children in emergency conditions, after blunt injuries to the abdominal cavity [10–12]. In the publication from 2008, Valentino presented studies conducted in 27 children (19 boys, 8 girls, mean age 8.9 years ± 2.8 [standard deviation]). In this group of patients, no adverse reaction was observed after the administration of SonoVue® [12]. Generally, revolutionary changes in ultrasound imaging that occurred due to ultrasound contrast agents, do not concern pediatric diagnostics. Potential benefits, such as limited ionizing radiation thanks to a lower number of CT and standard cystourethrography scans, no need for sedation in the case of smaller children, reproducibility or lower costs of the examination compared to CT and MRI, are commonly known. It should be underscored that it is of utmost importance in the diagnostics of this group of patients to improve the sensitivity and specificity of the examination, which should allow for a more rapid and adequate diagnosis. The experiences with UCAs in adults, especially excellently documented examination of liver changes, could be easily applied to children [13–16]. The possibility of bedside examinations is also important, especially in the ICU or in the case of children with hemato-oncological diseases. In cancer patients, second-generation UCAs would allow for the evaluation of the vasculature pattern within a tumor and monitoring of the response to initial chemotherapy introduced before a planned surgery. It seems that a more precise evaluation of the vascularization pattern of lymph nodes would be useful in the assessment of the primary and secondary lesions within the lymphatic system [17]. Moreover, it would also be possible to evaluate complications of anti-cancer treatment, i. e. residual lesions or evaluation of the central venous access in case of problems other than infectious complications. Taking into consideration only this small but significant (from the point of view of pediatric diagnostics) group of potential advantages of the second-generation UCAs, we should try to answer the question: “why do we refuse to provide children with better and more precise diagnostic procedures?”. We realize that this question tends to be rhetorical and controversial for the time being. However, the constant development of this

The accuracy of BI-RADS classification of breast ultrasound as a first-line imaging method.

Abstract: Purpose The aim was to evaluate the accuracy of BI-RADS categories 3 - 5 in breast ultrasound (US) as the first-line imaging method. Materials and methods 5077 examinations of a consecutive, unselected and mixed collective of symptomatic and asymptomatic patients were performed. Of these examinations, 835 cases of BIRADS 3 - 5 could be analyzed. Results The PPV with respect to a malignant lesion for BI-RADS 3, 4, 5 was 0.03, 0.48, and 0.97, respectively. When BI-RADS 4 and 5 cases are considered to be suspicious, the ratio of benign to malignant findings corresponds to 1:1.8. Analyzing BIRADS 3 - 5 lesions, the sensitivity, specificity and accuracy are 0.92, 0.85, and 0.87, respectively. Conclusion The data support the feasibility of US for discriminating malignant from benign findings corresponding to the ACR BI-RADS classification without excessively increasing the number of unnecessary biopsies.

Contrast-enhanced ultrasonography is more sensitive than grayscale and power Doppler ultrasonography compared to MRI in therapy monitoring of rheumatoid arthritis patients.

Abstract: PURPOSE To evaluate wrist and finger joints in patients with rheumatoid arthritis (RA) by grayscale, power Doppler (PD) and contrast-enhanced musculoskeletal ultrasonography (US) and to compare these findings with MRI, clinical (DAS28) and laboratory (ESR; CRP) data. MATERIALS AND METHODS US was performed at baseline (t0) and after three, six and twelve (t12) months before and after a change of medical treatment. MRI was carried out at t0 and t12 and used as the reference method. Contrast-enhanced US was used to assess one clinically most affected joint region. Different semiquantitative synovitis scores were calculated by grayscale and PD US. RESULTS Contrast-enhanced US results evaluated by enhancement, slope and semi-quantitative assessment significantly correlated to each other, to grayscale US, CRP, as well as to MRI with the highest correlation coefficients for the used contrast-enhanced US modes (r = 0.56, r = 0.55, r = 0.57; each p < 0.05). Sum scores evaluated by grayscale US showed that synovial inflammation in finger joints was detected significantly more frequently in the palmar aspect than on the dorsal side (p = 0.001). Using power Doppler US, the wrists were significantly more inflamed from dorsal than on the palmar side (p = 0.0004). Significant longitudinal correlations between grayscale and power Doppler US scores were detected. CONCLUSION Grayscale, power Doppler and contrast-enhanced US are accurate tools for the detection and follow-up of synovitis in RA wrist and finger joints, with contrast-enhanced US being most sensitive compared to MRI. All imaging methods reflected a good response to TNFα blocking therapy.

Incidentally Detected Splenic Lesions in Ultrasound: Does Contrast-Enhanced Ultrasonography Improve the Differentiation of Benign Hemangioma/Hamartoma from Malignant Lesions?

Abstract: PURPOSE: The aim of the study was to identify and validate enhancing features for differentiating benign vascular neoplasms of the hemangioma/hamartoma type from malignant splenic lesions on contrast-enhanced ultrasonography (CEUS). MATERIALS AND METHODS: 136 splenic lesions (58 benign vascular neoplasms, 78 malignant) in 136 patients underwent baseline US and pulse-inversion CEUS after sulfur hexafluoride-filled microbubble injection. Two on-site readers assessed lesion enhancement features during arterial and parenchymal phase in consensus. Best predicting CEUS features for lesion diagnosis were identified through univariate and multivariate analyses. Two blinded off-site readers independently issued a confidence rating for lesion diagnosis in baseline US and CEUS using extracted diagnostic CEUS features. Diagnostic performance, receiver operating curves (Az-value), and interreader agreement were calculated. The reference standards were histopathology or CT and/or MR imaging with clinical follow-up. RESULTS: Multivariate analysis outlined arterial hyperenhancement or isoenhancement to be an independent CEUS predictor of benign vascular neoplasms (odds ratio, 3.558; p < 0.0017). Within the subgroup of isoechoic or hypoechoic lesions, arterial hyperenhancement was virtually diagnostic for benign vascular neoplasm (odds ratio, 21.333; p < 0.001). The diagnostic accuracy and confidence (Az-value) of the two readers was 63.2 % and 70.6 % (0.785 and 0.818) for baseline US, which improved significantly to 87.5 % and 88.2 % (0.915 and 0.908) for CEUS (p < 0.001). Interreader agreement also increased with CEUS (қ = 0.88) compared to baseline US (қ = 0.52). CONCLUSION: Sulfur hexafluoride-enhanced CEUS improves differentiation between benign vascular and malignant splenic tumors and may be especially useful in clinical scenarios in which the incidental hypoechoic splenic lesion is unclear on conventional US.

Relevance and methods of interventional breast sonography in preoperative axillary lymph node staging.

Abstract: Reduction of therapy-induced morbidity is an important goal for the improvement of the quality of breast cancer treatment. The introduction of sentinel lymph node biopsy (SLNB) significantly contributed to the reduction of surgery-induced morbidity in the shoulder-arm region. However, a clinically positive nodal status is still considered a contra-indication for SLNB. The current data constellation clearly shows that the clinical and also the sonographic malignancy assessment is insufficient for the accurate identification of the nodal status. A merely clinical and/or image-based appraisal of the axillary lymph node status would lead to overtreatment due to unnecessary axillary dissection in approximately 40 % of patients. In order to reduce the rate of unnecessary axillary dissection (AD), pretreatment interventional clarification is necessary to provide more detailed information about the histological condition of the lymph node. Comparing the currently available methods, fine needle aspiration (FNA) is the best in terms of cost and time requirement, practicability and complication rate. However, considering the sensitivity, it is inferior to ultrasound-guided core needle biopsy (CNB). Thus, a negative FNA outcome requires further clarification, which possibly can be performed with CNB. With a specificity of nearly 100 % and therefore a low rate of false positive cases for FNA, complete AD can be indicated by a positive FNA result. In the context of the interventional procedure, it must be stressed that FNA requires a high level of expertise on the part of both the examiner and the cytologist. The prerequisite for optimal interventional diagnostics of lymph nodes is an adequate sonographic assessment on the basis of standardized sonomorphological criteria.

[Diagnostic value of transthoracic ultrasound compared to chest radiography in the detection of a post-interventional pneumothorax].

Abstract: Purpose Chest radiography is standard for the diagnosis of a pneumothorax. However, also ultrasound of the chest has considerable value in the detection of a pneumothorax. A typical sonographic feature is the lack of the lung gliding sign. Aim of our trial was to evaluate the significance of ultrasound of the chest in the diagnosis of a pneumothorax supplemented by using power colour Doppler imaging. Patients and methods Following transbronchial biopsy, patients received transthoracic ultrasound of the chest for evaluation of a pneumothorax. Immediately afterwards, a chest radiograph was performed and results were compared. Results 1023 patients (321 female, 702 male, median age 47 years) were examined. In 30 patients (2.9%) chest radiograph revealed a pneumothorax, while in ultrasound of the chest a pneumothorax was diagnosed in 36 of the cases. Defining chest radiography as gold standard, ultrasound of the chest had a sensitivity of 100%, a specificity of 83% and an accuracy of 99%. Conclusion Transthoracic ultrasound of the chest is a highly sensitive and specific diagnostic tool in the diagnosis of a pneumothorax. In comparison to chest radiography, it is better available and prevents administration of ionizing radiation. However, a disadvantage of ultrasound is the lack of quantification of a pneumothorax and the assessment of the indication for chest tube drainage.

Differentiation between phyllodes tumor and fibroadenoma using real-time elastography.

Abstract: Purpose: Phyllodes tumors (PT) are a rare entity accounting for less than 1 % of all breast lesions. They have a malignancy rate of 25 – 30 %. Differentiation from benign fibroadenomas is difficult using ultrasound, mammogram and MRI. The elastic characteristics of both tumors were examined using real-time elastography (RTE) to find specific patterns that make differentiation possible. Materials and Methods: From February 2007 to May 2009, a total of 620 women were examined by RTE. Histological diagnosis was achieved using core needle biopsy. 123 of the lesions were fibroadenomas, 8 were phyllodes tumors. All patients underwent mammography and ultrasound followed by RTE. Sonography was performed by Acuson Antares, Premium Edition® (Siemens, Erlangen, Germany) with a 7 and 10 MHz transducer. Results: All phyllodes tumors had a similar elastic pattern with an elastic center and inelastic outer limits, referred to as the “ring sign”. It was found in 5 % of all fibroadenomas. Conclusion: RTE provides a specific elastic pattern, which is sufficient for differentiating between a fibroadenoma and a phyllodes tumor. Therefore, the detection of the most suspicious lesion in women with the coexistence of multiple fibroadenomas and phyllodes tumors seems easier.

Contrast-enhanced ultrasound (CEUS) for differentiating between hepatocellular and cholangiocellular carcinoma.

Abstract: Purpose: HCC and CC are the most common primary malignancies of the liver. There is only minimal evidence as to whether these two entities can be reliably differentiated by contrast-enhanced ultrasound. Materials and Methods: We retrospectively analyzed the CEUS pattern of 39 patients with HCC, 11 patients with intrahepatic cholangiocarcinoma (ICC), 3 patients with Klatskin tumor, and 4 patients with gallbladder carcinoma. CEUS was performed using a standardized protocol (low MI, SonoVue®) with documentation of the arterial, portal-venous, and late phase. Besides the contrast enhancement compared to the adjacent normal liver tissue in every phase, the specific contrast pattern during the arterial phase (complete filling, incomplete filling of different grade, rim sign) was analyzed. Results: Most HCC and ICC showed hyperenhancement during the arterial phase, with hypoenhancement or isoenhancement in the portal-venous and late phase. Hyperenhancement during the portal-venous phase was only observed in some cases of HCC, but not in ICC. In the case of arterial hyperenhancement, HCC showed complete filling more often than ICC. In the case of incomplete filling, the area of contrast-enhanced tumor in most HCCs was larger than in ICCs. A rim sign was present in only less than half ICCs, but in no HCCs. Conclusion: HCC and ICC differ to some extent in their CEUS enhancement pattern. Incomplete arterial hyperenhancement is more often seen in ICC than in HCC. A rim sign seems to be specific for ICC, but is only rarely present. However, in a case-to-case decision, due to overlapping characteristics, a reliable differentiation between the two tumor types by CEUS alone is very often not possible.