[The first experience in using elastography in combination with endobronchial ultrasonography for mediastinal pathology: Preliminary assessment of feasibility and comparison of characteristics via different approaches].

OBJECTIVE: To preliminarily assess the feasibility of elastography in endobronchial ultrasonography and to compare characteristics via different accesses. MATERIAL AND METHODS: The investigation enrolled 3 patients (malignant, benign mediastinal adenopathy, paratracheal tumor). Elastography was carried out using a Pentax EB-1970UK echobronchoscope with a Hitachi Noblus ultrasound scanner. All the patients underwent fine-needle aspiration biopsy of mediastinal and pulmonary lymph nodes/masses with 22G needles (Cook, Medi-Globe). Sequential study of the same group of lymph nodes through different approaches through the esophagus and trachea was conducted, and its characteristics were compared in one patient. RESULTS: A total of 8 lymph nodes and one paratracheal mass (Group 4L-7-4R-2R) were assessed in three patients. Reproducible images acceptable for visual assessment were obtained in all cases. The wall of the trachea and bronchi had no significant negative impact on the quality of an obtained image. Both malignant lesion of lymph nodes and paratracheal mass was accompanied by decreased tissue elasticity in the area of interest. Assessment of the same benign lymph node through different approaches revealed a clear discordance between elastographic findings with a drastic decrease in elasticity values via an endobronchial approach. CONCLUSION: Endobronchial ultrasonography elastography is technically feasible. The wall of the trachea and bronchi has no significant impact on the quality of an obtained image; elastographic data are reproducible during re-measurements. Comparison of elastographic characteristics through different approaches suggests that there is a tendency to overestimate data on lymph node density during endobronchial examination versus a transesophageal approach. Thus, the direct transfer of the accumulated data and patterns of elastographic diagnosis to an endobronchial approach is impossible and likely to require a revision of criteria to estimate malignancy-associated changes during its application.

[Challenges and opportunities for endoscopic ultrasound in the preoperative diagnosis of topical insulin the pancreas].

Insulinoma in most cases is monohormonal orthoendocrine tumor. This fact limits its searching area by a pancreas. However the insulinoma's clinical picture can be caused by other pathology. Therefore the main task of visual the tumor but also to use all the possibilities of each method for defining type of surgery and avoiding such errors and complications, as pancreatorrhage, damage of bile or pancreatic duct, necrosis of duodenal wall, etc. On the basis of our own experience of endoscopic ultrasound for 61 patients with 66 insulinomas, we have allocated the basic variants of insulinoma ultrasound pictures: hypoechoic, heteroechoic, isoechoic tumor, and also foci without a trustworthy contour. On the basis of the analysis of our own errors we have essentially added the technique, having used multiplane pancreas scanning and biplane tumor scanning. Important points in EUS algorithm are also the following items: detecting tumor relationship to pancreatic surface, distance from the tumor to the ducts, gastrointestinal wall and vessels--for definition of possibility of the tumor enucleation; careful scanning of pancreas even after detecting one tumor--for an exception of multiple tumors, especially at MEN-I; careful scanning of a contour of the gland for an exception of parapancreatic insulinomas; estimation of vascularization not only of the detected tumor and suspicious foci, but also of all the gland--for detection of hypervascularized isoechoic tumors; revealing and the description of focal changes, especially more homoechogeneous in comparison with surrounding parenchyma-- for selection patients for examination by other methods; scanning of zones of possible metastasis. Examination of patients with organic hyperinsulinism demands combined application of two or more techniques. Use of all modern possibilities of endosonography can put this technique on one of the first places in the diagnosis of insulinomas.