Background The role of EUS with contrast agents can be expanded through the use of time-intensity curve (TIC) analysis and computer-aided interpretation. Objective To validate the use of parameters ...derived from TIC analysis in an artificial neural network (ANN) classification model designed to diagnose pancreatic carcinoma (PC) and chronic pancreatitis (CP). Setting Prospective, multicenter, observational trial—endoscopy units from Romania, Denmark, Germany, and Spain. Patients A total of 167 consecutive patients with PC or CP. Interventions Contrast-enhanced harmonic EUS (CEH-EUS) and EUS-guided FNA (EUS-FNA), TIC analysis, and ANN processing. Main Outcome Measurements Sensitivity, specificity, positive and negative predictive values (PPV, NPV) for EUS-FNA, CEH-EUS, and the ANN. Results After excluding all of the recordings that did not meet the technical and procedural criteria, 112 cases of PC and 55 cases of CP were included. EUS-FNA was performed in 129 patients, and the diagnosis was confirmed by surgery (n = 15) or follow-up (n = 23) in the remaining cases. Its sensitivity and specificity were 84.82% and 100%, respectively, whereas the PPV and NPV were 100% and 76.63%, respectively. The sensitivity of real-time quantitative assessment of CEH-EUS was 87.5%, specificity 92.72%, PPV 96.07%, and NPV 78.46%. Peak enhancement, wash-in area under the curve, wash-in rate, and the wash-in perfusion index were significantly different between the groups. No significant differences were found between rise time, mean transit time, and time to peak. For the ANN, sensitivity was 94.64%, specificity 94.44%, PPV 97.24%, and NPV 89.47%. Limitations Only PC and CP lesions were included. Conclusion Parameters obtained through TIC analysis can differentiate between PC and CP cases and can be used in an automated computer-aided diagnostic system with good diagnostic results. (Clinical trial registration number: NCT01315548 .)
Ultrasound elastography (USE) of the pancreas allows pancreatic tissue stiffness assessment by virtual palpation. Two main types of USE are used. For the pancreas strain elastography applying by ...endoscopic ultrasound has been established for the characterisation of small solid pancreatic lesions (SPL). In larger SPL >30 mm the results are less convincing mainly due to the heterogenicity of the lesions but also by concomitant changes of the surrounding pancreatic parenchyma. The current role of shear wave elastography has to be determined. This article reviews the current use of elastography of the pancreas.
AIM： To evaluate the contrast-enhanced endosonography as a method of differentiating inflammation from pancreatic carcinoma based on perfusion characteristics of microvessels. METHODS： In 86 patients ...with suspected chronic pancreatitis （age： 62± 12 years; sex： f/m 38/48）, pancreatic lesions were examined by conventional endo- scopic B-mode, power Doppler ultrasound and contrastenhanced power mode （Hitachi EUB 525, SonoVue, 2.4 mL, Bracco） using the following criteria for malignant lesions： no detectable vascularisation using conventional power Doppler scanning, irregular appearance of arterial vessels over a short distance using SonoVue contrastenhanced technique and no detectable venous vessels inside the lesion. A malignant lesion was assumed if all criteria were detectable gold standard endoscopic ultrasound （EUS）-guided fine needle aspiration cytology, operation. The criteria of chronic pancreatitis without neoplasia were defined as no detectable vascularisation before injection of SonoVue, regular appearance of vessels over a distance of at least 20 mm after injection of SonoVue and detection of arterial and venous vessels. RESULTS： The sensitivity and specifidty of conventional EUS were 73.2% and 83.3% respectively for pancreatic cancer. The sensitivity of contrast-enhanced EUS increased to 91.1% in 51 of 56 patients with malignant pancreatic lesion and the specificity increased to 93.3% in 28 of 30 patients with chronic inflammatory pancreatic disease.CONCLUSION： Contrast-enhanced endoscopic ultrasound improves the differentiation between chronic pancreatitis and pancreatic carcinoma.
Background and Aims Pancreatic ductal adenocarcinoma (PDAC) is typically diagnosed at a late stage. Little is known about the incidental finding of early-stage PDAC. The aim of the current study was ...to determine the etiology of small solid pancreatic lesions (≤15 mm) to optimize clinical management. Methods Inclusion criterion for the retrospective study analysis was the incidental finding of primarily undetermined small solid pancreatic lesions ≤15 mm in 394 asymptomatic patients. Final diagnoses were based on histology or cytology obtained by imaging-guided biopsy (and at least 12-month follow-up) and/or surgery. Contrast-enhanced US or contrast-enhanced EUS were performed in 219 patients. Results The final diagnoses of 394 patients were as follows: 146 PDAC, 156 neuroendocrine tumors, 28 metastases into the pancreas from other primary sites, and 64 various other etiologies. Contrast-enhanced US allowed differential diagnosis of PDAC and non-PDAC in 189 of 219 patients (86%). Conclusions Approximately 40% of patients with small solid pancreatic lesions had very early stage PDAC. Approximately 60% of small solid pancreatic lesions ≤15 mm are not PDAC and, therefore, do not require radical surgery. Without preoperative diagnosis, an unacceptably large proportion of patients would be exposed to radical surgery with significant morbidity and mortality.
Background & Aims By using strain assessment, real-time endoscopic ultrasound (EUS) elastography provides additional information about a lesion's characteristics in the pancreas. We assessed the ...accuracy of real-time EUS elastography in focal pancreatic lesions using computer-aided diagnosis by artificial neural network analysis. Methods We performed a prospective, blinded, multicentric study at of 258 patients (774 recordings from EUS elastography) who were diagnosed with chronic pancreatitis (n = 47) or pancreatic adenocarcinoma (n = 211) from 13 tertiary academic medical centers in Europe (the European EUS Elastography Multicentric Study Group). We used postprocessing software analysis to compute individual frames of elastography movies recorded by retrieving hue histogram data from a dynamic sequence of EUS elastography into a numeric matrix. The data then were analyzed in an extended neural network analysis, to automatically differentiate benign from malignant patterns. Results The neural computing approach had 91.14% training accuracy (95% confidence interval CI, 89.87%–92.42%) and 84.27% testing accuracy (95% CI, 83.09%–85.44%). These results were obtained using the 10-fold cross-validation technique. The statistical analysis of the classification process showed a sensitivity of 87.59%, a specificity of 82.94%, a positive predictive value of 96.25%, and a negative predictive value of 57.22%. Moreover, the corresponding area under the receiver operating characteristic curve was 0.94 (95% CI, 0.91%–0.97%), which was significantly higher than the values obtained by simple mean hue histogram analysis, for which the area under the receiver operating characteristic was 0.85. Conclusions Use of the artificial intelligence methodology via artificial neural networks supports the medical decision process, providing fast and accurate diagnoses.
Strain Elastography - How To Do It? Dietrich, Christoph F.; Barr, Richard G.; Farrokh, André ...
Ultrasound international open,
09/2017, Letnik:
3, Številka:
4
Journal Article
Recenzirano
Odprti dostop
Abstract
Tissue stiffness assessed by palpation for diagnosing pathology has been used for thousands of years. Ultrasound elastography has been developed more recently to display similar information ...on tissue stiffness as an image. There are two main types of ultrasound elastography, strain and shear wave. Strain elastography is a qualitative technique and provides information on the relative stiffness between one tissue and another. Shear wave elastography is a quantitative method and provides an estimated value of the tissue stiffness that can be expressed in either the shear wave speed through the tissues in meters/second, or converted to the Young’s modulus making some assumptions and expressed in kPa. Each technique has its advantages and disadvantages and they are often complimentary to each other in clinical practice. This article reviews the principles, technique, and interpretation of strain elastography in various organs. It describes how to optimize technique, while pitfalls and artifacts are also discussed.
Background & Aims: Endoscopic ultrasound is a widely accepted imaging method for staging of ductal adenocarcinoma and the localization of neuroendocrine tumors of the pancreas. We prospectively ...evaluated conventional color Doppler imaging and contrast-enhanced endoscopic Doppler ultrasound (CE-EDUS) as a new imaging technique for further characterization and differentiation of solid pancreatic tumors. Methods: From 300 patients with pancreatic lesions investigated using contrast-enhanced endoscopic ultrasound we could finally include 93 patients with an undetermined, solitary, predominantly solid, lesion 40 mm or less, and a definite histologically proven diagnosis. After bolus injection of the contrast agent SHU 508A 4 g (400 mg/dL) the vascular pattern of the lesion during the arterial phase was compared with the vascularity of the residual pancreatic parenchyma. Results: Color Doppler imaging did not reveal vascularity of the pancreatic parenchyma in any of the patients, and therefore tumor hypovascularity could not be determined in contrast to all CE-EDUS–examined patients revealing at least some degree of parenchymal vascularity. Fifty-seven of 62 patients with ductal adenocarcinoma of the pancreas showed a hypovascularity of the tumor using CE-EDUS. All other pancreatic lesions revealed an isovascular or hypervascular pattern using contrast-enhanced endoscopic ultrasound (20 neuroendocrine tumors, 10 serous microcystic adenomas, and 1 teratoma). Hypovascularity as a sign of malignancy in contrast-enhanced endoscopic ultrasound obtained 92% (82%–97%) sensitivity and 100% specificity (89%–100%). Conclusions: Contrast-enhanced endoscopic ultrasound is effective in differentiating small solid pancreatic tumors of different origin in most cases. Hypovascularity indicates malignancy of pancreatic tumors.
Serous pancreatic neoplasia, data and review Dietrich, Christoph F; Dong, Yi; Jenssen, Christian ...
World journal of gastroenterology : WJG,
08/2017, Letnik:
23, Številka:
30
Journal Article
Odprti dostop
AIM To describe the imaging features of serous neoplasms of the pancreas using ultrasound, endoscopic ultrasound, computed tomography and magnetic resonance imaging.METHODS This multicenter ...international collaboration enhances a literature review to date, reporting features of 287 histologically confirmed cases of serous pancreatic cystic neoplasms(SPN). RESULTS Female predominance is seen with most SPN presenting asymptomatically in the 5th through 7th decade. Mean lesion size was 38.7 mm, 98% were single, 44.2% cystic, 46% mixed cystic and solid, and 94% hypoechoic on B-mode ultrasound. Vascular patterns and contrast-enhancement profiles are described as hypervascular and hyperenhancing.CONCLUSION The described ultrasound features can aid differentiation of SPN from other neoplastic lesions under most circumstances.
In this 14th document in a series of papers entitled "
" we discuss various aspects of EUS-guided biliary drainage that are debated in the literature and in practice. Endoscopic retrograde ...cholangiography is still the reference technique for therapeutic biliary access, but EUS-guided techniques for biliary access and drainage have developed into safe and highly effective alternative options. However, EUS-guided biliary drainage techniques are technically demanding procedures for which few training models are currently available. Different access routes require modifications to the basic technique and specific instruments. In experienced hands, percutaneous transhepatic cholangiodrainage is also a good alternative. Therefore, in this paper, we compare arguments for different options of biliary drainage and different technical modifications.
Endoscopic ultrasound has become an essential tool in modern gastroenterology and abdominal surgery. Compared with all other endoscopic methods, it has the most potential for innovation and its ...future looks bright. Thus, we compiled this summary of established and novel applications of endoscopic ultrasound methods to inform the reader about what is already possible and where future developments will lead in improving patient care further. This review is structured in four parts. The first section reports on developments in diagnostic endoscopic ultrasound, the second looks at semi-invasive endoscopic ultrasound, and the third discusses advances in therapeutic endoscopic ultrasound. An overview on the future prospects of endoscopic ultrasound methods concludes this article.
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