Thoracic impedance pneumography in propofol-sedated patients undergoing percutaneous endoscopic gastrostomy (PEG) placement in gastrointestinal endoscopy: A prospective, randomized trial.

STUDY OBJECTIVE: To assess the efficacy of an ECG-based method called thoracic impedance pneumography to reduce hypoxic events in endoscopy. DESIGN: This was a single center, 1:1 randomized controlled trial. SETTING: The trial was conducted during the placement of percutaneous endoscopic gastrostomy (PEG). PATIENTS: 173 patients who underwent PEG placement were enrolled in the present trial. Indication was oncological in most patients (89%). 58% of patients were ASA class II and 42% of patients ASA class III. INTERVENTIONS: Patients were randomized in the standard monitoring group (SM) with pulse oximetry and automatic blood pressure measurement or in the intervention group with additional thoracic impedance pneumography (TIM). Sedation was performed with propofol by gastroenterologists or trained nurses. MEASUREMENTS: Hypoxic episodes defined as SpO2 < 90% for >15 s were the primary endpoint. Secondary endpoints were minimal SpO2, apnea >10s/>30s and incurred costs. MAIN RESULTS: Additional use of thoracic impedance pneumography reduced hypoxic episodes (TIM: 31% vs SM: 49%; p = 0.016; OR 0.47; NNT 5.6) and elevated minimal SpO2 per procedure (TIM: 90.0% ± 8.9; SM: 84.0% ± 17.6; p = 0.007) significantly. Apnea events >10s and > 30s were significantly more often detected in TIM (43%; 7%) compared to SM (1%; 0%; p < 0.001; p = 0.014) resulting in a time advantage of 17 s before the occurrence of hypoxic events. As a result, adjustments of oxygen flow were significantly more often necessary in SM than in TIM (p = 0.034) and assisted ventilation was less often needed in TIM (2%) compared with SM (9%; p = 0.053). Calculated costs for the additional use of thoracic impedance pneumography were 0.13$ (0.12 €/0.11 £) per procedure. CONCLUSIONS: Additional thoracic impedance pneumography reduced the quantity and extent of hypoxic events with less need of assisted ventilation. Supplemental costs per procedure were negligible. KEY WORDS: thoracic impedance pneumography, capnography, sedation, monitoring, gastrointestinal endoscopy, percutaneous endoscopic gastrostomy.

Impact of controlled attenuation parameter on detecting fibrosis using liver stiffness measurement.

BACKGROUND: Liver fibrosis is often accompanied by steatosis, particularly in patients with non-alcoholic fatty liver disease (NAFLD), and its non-invasive characterisation is of utmost importance. Vibration-controlled transient elastography is the non-invasive method of choice; however, recent research suggests that steatosis may influence its diagnostic performance. Controlled Attenuation Parameter (CAP) added to transient elastography enables simultaneous assessment of steatosis and fibrosis. AIM: To determine how to use CAP in interpreting liver stiffness measurements. METHODS: This is a secondary analysis of data from an individual patient data meta-analysis on CAP. The main exclusion criteria for the current analysis were unknown aetiology, unreliable elastography measurement and data already used for the same research question. Aetiology-specific liver stiffness measurement cut-offs were determined and used to estimate positive and negative predictive values (PPV/NPV) with logistic regression as functions of CAP. RESULTS: Two thousand and fifty eight patients fulfilled the inclusion criteria (37% women, 18% NAFLD/NASH, 42% HBV, 40% HCV, 51% significant fibrosis ≥ F2). Youden optimised cut-offs were only sufficient for ruling out cirrhosis (NPV of 98%). With sensitivity and specificity-optimised cut-offs, NPV for ruling out significant fibrosis was moderate (70%) and could be improved slightly through consideration of CAP. PPV for significant fibrosis and cirrhosis were 68% and 55% respectively, despite specificity-optimised cut-offs for cirrhosis. CONCLUSIONS: Liver stiffness measurement values below aetiology-specific cut-offs are very useful for ruling out cirrhosis, and to a lesser extent for ruling out significant fibrosis. In the case of the latter, Controlled Attenuation Parameter can improve interpretation slightly. Even if cut-offs are very high, liver stiffness measurements are not very reliable for ruling in fibrosis or cirrhosis.

Regression of fibrosis and portal hypertension in HCV-associated cirrhosis and sustained virologic response after interferon-free antiviral therapy.

It is still controversial, whether and to what amount cirrhosis and portal hypertension are reversible in patients with hepatitis C virus (HCV)-associated cirrhosis and sustained virologic response (SVR) after interferon-free antiviral therapy. In this study, we prospectively evaluated dynamics of liver and spleen stiffness in HCV-infected patients with advanced liver disease and SVR after interferon-free treatment. A total of 54 patients with HCV-associated cirrhosis and SVR were included. Liver and spleen stiffness was measured at therapy baseline (BL), end of treatment (EOT) and 24 weeks after EOT (FU24) by transient liver elastography (L-TE) as well as by acoustic radiation force impulse of the liver (L-ARFI) and spleen (S-ARFI), as well as biochemical, virologic and clinical data. Improvement of liver and spleen stiffness was found in 44 of 50 (88%), 31 of 54 (57%) and 25 of 54 (46%) of patients assessed by L-TE, L-ARFI and S-ARFI between baseline and FU24. Liver stiffness assessed by L-TE improved between BL [median (range), 32.5 (9.1-75) kPa] and EOT [median (range), 21.3 (6.7-73.5) kPa; (P<.0001)], and between BL and FU24 [median (range), 21.2 (5.4-70) kPa; (P<.0001)]. Liver stiffness assessed by L-ARFI improved between BL [median (range), 2.7 (1.2-4.1) m/s] and FU24 [median (range), 2.4 (1.2-3.9) m/s; P=.002), while spleen stiffness remained unchanged. Our data suggest that improvement of liver stiffness may be rather due to reduced necroinflammation and may be due to a less extent to regression of cirrhosis, as dynamics of liver stiffness improvement was more pronounced between BL and EOT than BL and FU24.

Evaluation of Strain Elastography for Differentiation of Thyroid Nodules: Results of a Prospective DEGUM Multicenter Study.

PURPOSE: Many patients with thyroid nodules are presently referred to surgery for not only therapeutic but also diagnostic purposes. The aim of noninvasive diagnostic methods is to optimize the selection of patients for surgery. Strain elastography (SE) enables the ultrasound-based determination of tissue elasticity. The aim of the present study was to evaluate the value of SE for the differentiation of thyroid nodules in a prospective multicenter study. MATERIALS AND METHODS: The study was registered at clinicaltrials.gov and was approved by the local ethics committees of all participating centers. All patients received an ultrasound (US) of the thyroid gland including color Doppler US. In addition, all nodules were evaluated by SE (Hitachi Medical Systems) using qualitative image interpretation of color distribution (SE-ES), strain value and strain ratio. RESULTS: Overall, 602 patients with 657 thyroid nodules (567 benign, 90 malignant) from 7 centers were included in the final analysis. The sensitivity, specificity, NPV, PPV, +LR were 21 %, 73 %, 86 %, 11 %, 0.8, respectively, for color Doppler US; 69 %, 75 %, 94 %, 30 %, 2.9, respectively, for SE-ES; 56 %, 81 %, 92 %, 32 %, 2.9, respectively, for SE-strain value; and 58 %, 78 %, 92 %, 30 %, 2.6, respectively, for SE-strain ratio. The diagnostic accuracy was 71 % for both strain value and strain ratio of nodules. CONCLUSION: SE as an additional ultrasound tool improves the value of ultrasound for the work-up of thyroid nodules. It might reduce diagnostic surgery of thyroid nodules in the future.

Point Shear Wave Elastography by Acoustic Radiation Force Impulse Quantification in Comparison to Transient Elastography for the Noninvasive Assessment of Liver Fibrosis in Chronic Hepatitis C: A Prospective International Multicenter Study.

PURPOSE: The aim of the present prospective European multicenter study was to demonstrate the non-inferiority of point shear wave elastography (pSWE) compared to transient elastography (TE) for the assessment of liver fibrosis in patients with chronic hepatitis C. MATERIALS AND METHODS: 241 patients with chronic hepatitis C were prospectively enrolled at 7 European study sites and received pSWE, TE and blood tests. Liver biopsy was performed with histological staging by a central pathologist. In addition, for inclusion of cirrhotic patients, a maximum of 10 % of patients with overt liver cirrhosis confirmed by imaging methods were allowed by protocol (n = 24). RESULTS: Owing to slower than expected recruitment due to a reduction of liver biopsies, the study was closed after 4 years before the target enrollment of 433 patients with 235 patients in the 'intention to diagnose' analysis and 182 patients in the 'per protocol' analysis. Therefore, the non-inferiority margin was enhanced to 0.075 but non-inferiority of pSWE could not be proven. However, Paired comparison of the diagnostic accuracy of pSWE and TE revealed no significant difference between the two methods in the 'intention to diagnose' and 'per protocol' analysis (0.81 vs. 0.85 for F ≥ 2, p = 0.15; 0.88 vs. 0.92 for F ≥ 3, p = 0.11; 0.89 vs. 0.94 for F = 4, p = 0.19). Measurement failure was significantly higher for TE than for pSWE (p = 0.030). CONCLUSION: Non-inferiority of pSWE compared to TE could not be shown. However, the diagnostic accuracy of pSWE and TE was comparable for the noninvasive staging of liver fibrosis in patients with chronic hepatitis C.

Incidence of bleeding in 8172 percutaneous ultrasound-guided intraabdominal diagnostic and therapeutic interventions - results of the prospective multicenter DEGUM interventional ultrasound study (PIUS study).

PURPOSE: To analyse the incidence of bleeding after percutaneous ultrasound guided diagnostic and therapeutic intraabdominal interventions in a prospective multicentre study (DEGUM percutaneous interventional ultrasound study). MATERIALS AND METHODS: Within a time period of 2 years diagnostic and therapeutic intraabdominal interventions (with the exclusion of ascites paracentesis) performed percutaneously under continuous ultrasound (US) guidance were prospectively assessed using a pseudonymized standardized web site entry form. Number and type of intervention, operator experience, patient characteristics, medication, lab data as well as technical aspects of the procedure and bleeding complications were analysed according to the interventional radiology standards. RESULTS: 8172 US-guided intraabdominal interventions (liver n = 5903; pancreas n = 501, kidney n = 434, lymph node = 272, biliary system n = 153, spleen n = 63, other abdominal organs and extra-organic targets n = 999) were analysed in 30 hospitals. The majority were diagnostic biopsies including 1780 liver parenchyma, 3400 focal liver lesions and 404 pancreatic lesions. 7525 interventions (92.1 %) were performed in hospitalized patients (mean age 62.6 years). Most operators were highly experienced in US-guided interventions (> 500 interventions prior to the study n = 5729; 70.1 %). Sedation was administered in 1131 patients (13.8 %). Needle diameter was ≥ 1 mm in 7162 punctures (87.9 %) with main focus on core needle biopsies (18 G, n = 4185). Clinically relevant bleeding complications with need of transfusion (0.4 %), surgical bleeding control (0.1 %) and radiological coiling (0.05 %) were very rare. Bleeding complications with fatal outcome occurred in four patients (0.05 %). The frequency of major bleeding complications was significantly higher in patients with an INR > 1.5 (p < 0.001) and patients taking a medication potentially interfering with platelet function or plasmatic coagulation (p < 0.0333). CONCLUSION: This prospective multicentre study confirms the broad spectrum of percutaneous US-guided intraabdominal interventions. However diagnostic liver biopsies dominate with the use of core needle biopsies (18 G). Percutaneous US-guided interventions performed by experienced sonographers are associated with a low bleeding risk. Major bleeding complications are very rare. A pre-interventional INR < 1.5 and individual medication risk assessment are recommended.

[Ultrasound after liver transplantation]. / Sonografie nach Lebertransplantation.

Graft specific complications after liver transplantation may be classified as vascular, biliar, and miscellaneous. This review provides an overview on sonography after liver transplantation.

Identifying indications for percutaneous (PTC) vs. endoscopic ultrasound (EUS)- guided "rendezvous" procedure in biliary obstruction and incomplete endoscopic retrograde cholangiography (ERC).

BACKGROUND: The variety of rendezvous (RV) procedures has recently been extended by EUS- and PTCD-guided procedures as a complementary means to conventional ERCP. We have identified indication criteria and the potential of biliary PTCD-guided vs. EUS-guided RV. METHODS: Consecutive patients with bile duct obstruction who underwent RV were included. In all, ERCP alone was unable to achieve treatment success. Indication, technical success, and outcome in PTCD- vs. EUS-guided RV were retrospectively compared to identify criteria that indicate preference of RV technique. Site of obstruction, clinical scenario (stenosis with abscess vs. no abscess) and reason for previous failure of ERC were evaluated. RESULTS: In 32 patients, three different indications for RV procedures were identified: First, a one-step access to assist in failed ERCP (type 1, intra-ductal RV); second, temporary drainage for prolonged treatment of complex biliary disease (type 2, intra-ductal RV), and drainage of cholangio-abscess with re-establishing bile outflow (type 3, intra-abscess RV). Indication of PTCD- vs. EUS-guided rendezvous was competitive in type 1, but exclusive in favor of PTCD in types 2 and 3. The site of biliary obstruction indicated the anatomic location of RV procedures. CONCLUSIONS: This classification may help to define inclusion criteria for prospective studies on biliary RV procedures. Choice of therapeutic strategy depends on the anatomic location of the biliary obstruction and the type of the biliary lesion. PTCD-guided RV might improve outcome in cholangio-abscess.

Self-expandable metal stent for malignant colonic obstruction: outcome in proximal vs. left sided tumor localization.

INTRODUCTION: The aim of this study was to evaluate the outcome of through-the-scope (TTS) implanted self-expanding metal stent (SEMS) comparing left-sided vs. proximal placement with regard to complications and outcome in palliation of malignant colorectal obstruction. MATERIAL AND METHODS: All patients were consecutively retrospectively enrolled to this study between January 2009 and February 2012 due to impending or prevalent complete malignant colorectal obstruction. TTS applicable uncovered nitinol SEMS with unique flexible properties were used (Taewoong Medical, South Korea). Left-sided obstruction (aboral from the left flexure) was compared to proximal (from the ileo-cecal valve to the left flexure) localization. All patients have been discussed in the interdisciplinary tumor conference and the recommendation to treat by endoscopic stent placement was given in consensus. RESULTS: A total of 15 patients was enrolled to this study (10 male and 5 female; mean age 68.3 ± 15.4 years, range 48 - 94), five patients with obstructions located in the proximal hemicolon whereas ten patients had a left-sided malignancy. Technical success was achieved in all cases and there was no early complication noticed. Three late complications included tumor overgrowth (n = 1), stent occlusion (1), and dislocation (1). Stent-in-stent insertion achieved, again, clinical success. The site of SEMS implantation (proximal vs. left colon) had no impact on patient outcome or complication rate. SEMS patency duration was 269.8 ± 175.2 days (range 30 - 570) and mean survival of the patients was 305.1 ± 279.3 days (range 16 - 990). CONCLUSION: TTS application of flexible, non-covered SEMS seems to be safe and effective for palliation of malignant colorectal obstruction independent of localization of the tumor in the colon.

EFSUMB guidelines and recommendations on the clinical use of ultrasound elastography. Part 2: Clinical applications.

The clinical part of these Guidelines and Recommendations produced under the auspices of the European Federation of Societies for Ultrasound in Medicine and Biology EFSUMB assesses the clinically used applications of all forms of elastography, stressing the evidence from meta-analyses and giving practical advice for their uses and interpretation. Diffuse liver disease forms the largest section, reflecting the wide experience with transient and shear wave elastography . Then follow the breast, thyroid, gastro-intestinal tract, endoscopic elastography, the prostate and the musculo-skeletal system using strain and shear wave elastography as appropriate. The document is intended to form a reference and to guide clinical users in a practical way.

EFSUMB guidelines and recommendations on the clinical use of ultrasound elastography. Part 1: Basic principles and technology.

The technical part of these Guidelines and Recommendations, produced under the auspices of EFSUMB, provides an introduction to the physical principles and technology on which all forms of current commercially available ultrasound elastography are based. A difference in shear modulus is the common underlying physical mechanism that provides tissue contrast in all elastograms. The relationship between the alternative technologies is considered in terms of the method used to take advantage of this. The practical advantages and disadvantages associated with each of the techniques are described, and guidance is provided on optimisation of scanning technique, image display, image interpretation and some of the known image artefacts.

Acoustic radiation force impulse imaging for non-invasive assessment of liver fibrosis in chronic hepatitis B.

Acoustic radiation force impulse (ARFI) imaging is a novel ultrasound-based elastography method that is integrated in a conventional ultrasound machine. It might provide an alternative method to transient elastography for the noninvasive assessment of liver fibrosis. While previous studies have shown comparable diagnostic accuracy of ARFI to transient elastography in chronic hepatitis C, the aim of the present prospective multicenter study was to evaluate ARFI for the assessment of liver fibrosis in chronic hepatitis B. ARFI imaging involves the mechanical excitation of tissue using short-duration acoustic pulses to generate localized displacements in tissue. The displacements result in shear-wave propagation which is tracked using ultrasonic, correlation-based methods and recorded in m/s. In the present international prospective study, patients infected with chronic hepatitis B received ARFI imaging, blood tests and if available transient elastography. The results were compared to liver biopsy as reference method analysed by a central pathologist. In 92 of 114 patients, a comparison of ARFI with transient elastography was possible. ARFI imaging and transient elastography correlated significantly with histological fibrosis stage. The diagnostic accuracy expressed as areas under ROC curves for ARFI imaging and transient elastography was 0.75 and 0.83 for the diagnosis of significant fibrosis (F ≥ 2), 0.93 and 0.94 for the diagnosis of severe fibrosis (F ≥ 3), and 0.97 and 0.93 for the diagnosis of liver cirrhosis, respectively. No significant difference was found between ARFI and transient elastography. ARFI imaging is a reliable ultrasound-based method for the assessment of advanced stages of liver fibrosis in chronic hepatitis B.

[Non-invasive methods for the evaluation of liver fibrosis in clinical practice]. / Nicht-invasive Verfahren zur Bestimmung der Leberfibrose in der klinischen Praxis.

Staging of the degree of liver fibrosis is important for the estimation of prognosis, surveillance and treatment decision in patients with chronic liver diseases. At present, liver biopsy is still the reference standard for the assessment of liver fibrosis. However, it is an invasive method with respective complications and limitations. Thus, non-invasive methods such as blood fibrosis markers and ultrasound-based elastography methods have been intensively evaluated for the assessment of liver fibrosis. The aim of the present article is to give an overview of research and clinical applicability of non-invasive methods in chronic liver disease.

Performance of Acoustic Radiation Force Impulse imaging for the staging of liver fibrosis: a pooled meta-analysis.

Acoustic Radiation Force Impulse (ARFI) imaging is a novel ultrasound-based elastography method that is integrated in a conventional ultrasound machine enabling the exact localization of measurement site. It might present an alternative method to transient elastography for the noninvasive assessment of liver fibrosis. At present, studies with small patient population have shown promising results. A systematic review and meta-analysis of pooled patient data were performed to evaluate the overall performance of ARFI for the staging of liver fibrosis. Literature databases were searched up to 10/2010. The authors of the original publication were contacted, and the original patient data were requested. A meta-analysis was performed using a random effect meta-analytic method for diagnostic tests. In addition, available data comparing ARFI with FibroScan with the DeLong test were evaluated. Literature search yielded nine full-paper publications evaluating ARFI while using liver biopsy as reference method. Original patient data were available from eight studies including 518 patients. The mean diagnostic accuracy of ARFI expressed as areas under ROC curves (AUROC) was 0.87 for the diagnosis of significant fibrosis (F ≥ 2), 0.91 for the diagnosis of severe fibrosis (F ≥ 3), and 0.93 for the diagnosis of cirrhosis. ARFI can be performed with good diagnostic accuracy for the noninvasive staging of liver fibrosis.

Peroral cholangioscopy for diagnosis and therapy of biliary tract disease using an ultra-slim gastroscope.

High-resolution video cholangioscopy is expected to improve diagnostic validity for diseases of the biliary tract. We report our experience in using an ultra-slim gastroscope for diagnosis and treatment of biliary tract disease. Cholangioscopy was attempted in 25 cases (22 patients) and succeeded in 22 cases (success rate 88%; 19 patients). Cholangiocellular carcinoma (CCC) was diagnosed by cholangioscopy in five of 10 cases (histopathologically confirmed in four), or ruled out in five. Cholangioscopy was used to detect stones in mega-choledochus (n=3), to clarify the postoperative condition of the bile ducts (n=2), to diagnose bile duct varices (n=1), and to release a dislodged self-expanding metal stent (n=1), and others. Argon plasma coagulation was successfully completed in a patient with mucin-producing adenomatosis of the bile ducts. One case of non-fatal air embolism occurred before replacing air with CO2 insufflation. In summary, peroral cholangioscopy with an ultra-slim gastroscope is feasible and helpful in selected patients, improving diagnostic validity, and offering new therapeutic interventions. This technique should only be performed using CO2 insufflation.

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

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 I&II were seen in all patients with primary or secondary malignant lesions of the adrenal gland (n = 16). The sensitivity and specificity of CEUS for the diagnosis of malignant adrenal mass were 100 % (CI [75;100]) 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.

Contrast-enhanced ultrasound (CEUS) for the characterization of focal liver lesions in clinical practice (DEGUM Multicenter Trial): CEUS vs. MRI--a prospective comparison in 269 patients.

PURPOSE: The aim of this prospective multicenter study was to assess the diagnostic role of CEUS in the diagnosis of newly discovered focal liver lesions in clinical practice. One important aspect is the comparison of CEUS with magnetic resonance imaging (MRI). MATERIALS AND METHODS: From 05 / 2004 to 12 / 2006, standardized CEUS was performed prospectively on 1349 patients with focal liver lesions that had been newly detected by fundamental ultrasound in order to determine tumor differentiation and tumor entity. 269 patients had a standardized MRI after CEUS. In typical liver hemangioma and focal nodular hyperplasia (FNH), the definitive diagnosis was based on the MRI as the "diagnostic gold standard" and on clinical evidence and additional follow-up (subgroup A) or on histology (subgroup B). 262 patients met the diagnostic standard that had been set. RESULTS: In the subcollective (n = 262), the tumor differentiation (malignant or benign) of CEUS and MRI was concordant in 225 cases (85.9%), and the assessment of tumor entity in 204 cases (77.9%). In subgroup A (n = 180), concordant results for tumor differentiation were obtained in 169 (93.2%) and for tumor entity in 160 (88.9%) cases. Liver hemangiomas (n = 122) and FNH (n = 43) were most frequent. Subgroup B (n = 82) comprised mainly malignant liver lesions (n = 55), with only a few of hemangiomas (n = 8) or FNH (n = 5). Tumor differentiation was concordant in 56 (68.3%) and tumor entity in 44 cases (53.7%). There were no statistically proven differences between CEUS and MRI. CONCLUSION: CEUS and MRI are of equal value for the differentiation and specification of newly discovered liver tumors in clinical practice. CEUS and MRI are extremely reliable for the differentiation of benign and malignant lesions, the diagnosis of liver hemangiomas and FNH. The characterization of metastases and HCC is also very reliable.

Real-time elastography and contrast-enhanced ultrasound for the assessment of thyroid nodules.

OBJECTIVE: Work-up of thyroid nodules remains challenging. Recent technologies enable determination of tissue elasticity and perfusion using ultrasound devices. The aim of the present study was to evaluate real-time elastography (RTE) and contrast-enhanced ultrasound with Sonovue (CEUS) for the differentiation of benign and malignant thyroid nodules. MATERIALS AND METHODS: Inclusion criteria were: nodules ≥1 cm, non-functioning or hypo-functioning on radionuclide scanning, and cytological/histological assessment. All patients received conventional ultrasound, RTE and CEUS. RTE was classified as: Elasticity-Score (ES)1 = soft, ES2 = predominantly soft, ES3 = predominantly hard, ES4 = hard nodule. CEUS-video clips were digitally recorded and analyzed using time-intensity-curves within selected regions-of-interest. RESULTS: Fifty-three nodules in 50 patients were available for analysis. Forty-six nodules were benign on cytology/histology, 6 nodules were papillary carcinoma and one nodule was a follicular carcinoma. Nodule margin irregularity was the ultrasound pattern most predictive of malignancy with sensitivity 57% (95% confidence interval: 18-90%) and specificity 85% (71-94% p<0.05). When using ES3&4 for the diagnosis of malignant nodules sensitivity and specificity were 86% (42-99.7%) and 87% (75-95%), respectively (p = 0.0003). The only malignant nodule missed with RTE was a follicular carcinoma. Sensitivity for the diagnosis of papillary carcinoma therefore was 100%. No specific CEUS pattern could be identified to differentiate between benign and malignant nodules. CONCLUSIONS: RTE seems to be a useful tool in the work-up of thyroid nodules to exclude papillary thyroid cancer. However, follicular carcinoma remains a challenging problem. CEUS did not improve the characterization of thyroid nodules in this preliminary study.

Real-time tissue elastography versus FibroScan for noninvasive assessment of liver fibrosis in chronic liver disease.

PURPOSE: Transient elastography (FibroScan, [TE]) and serum fibrosis markers such as the FibroTest (FT) are established methods for the noninvasive staging of liver fibrosis. A study using real-time elastography (HI-RTE), which is integrated in a conventional ultrasound system, was recently published with comparable results to transient elastography. The aim of the present study was to validate real-time elastography using the formulas calculated in previous studies and to compare the results to transient elastography and FibroTest for the noninvasive assessment of liver fibrosis. MATERIALS AND METHODS: One hundred and thirty-four patients with chronic liver disease and either histological assessment of liver fibrosis (n = 112) or proven liver cirrhosis (n = 22) were included in the study. All patients received TE, HI-RTE, and biochemical evaluation on the same day as presentation. The calculation of the elasticity score of real-time elastography was performed in accordance with the two previously published studies. RESULTS: The Spearman correlation coefficient between transient elastography, real-time elastography and FibroTest with the histological Chevallier score was statistically significant with 0.78, 0.34, and 0.67, respectively (p < 0.01). The diagnostic accuracy expressed as areas under ROC curves was 0.84, 0.69 and 0.85 for the diagnosis of significant fibrosis (F > or = 2), and 0.97, 0.65, and 0.83 for the diagnosis of cirrhosis, respectively. CONCLUSION: Real-time elastography in its present form cannot replace transient elastography for noninvasive assessment of liver fibrosis.

Tumor-specific vascularization pattern of liver metastasis, hepatocellular carcinoma, hemangioma and focal nodular hyperplasia in the differential diagnosis of 1,349 liver lesions in contrast-enhanced ultrasound (CEUS).

AIM: 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. MATERIALS AND METHODS: 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. RESULTS: 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. CONCLUSION: 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.