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Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jan 7, 2017; 23(1): 25-41
Published online Jan 7, 2017. doi: 10.3748/wjg.v23.i1.25
Maximizing the endosonography: The role of contrast harmonics, elastography and confocal endomicroscopy
Andrada Seicean, Ofelia Mosteanu, Radu Seicean
Andrada Seicean, Ofelia Mosteanu, Regional Institute of Gastroenterology and Hepatology Cluj-Napoca, University of Medicine and Pharmacy “Iuliu Hatieganu”, 400162 Cluj-Napoca, Romania
Radu Seicean, First Surgical Clinic Cluj-Napoca, University of Medicine and Pharmacy “Iuliu Hatieganu”, 400162 Cluj-Napoca, Romania
Author contributions: Seicean A conceived and designed the study; Seicean A, Mosteanu O and Seicean R analyzed and interpreted the data, drafted the article, and gave their approval for the final version of the article to be published.
Supported by National Grant of the Romanian Education Ministry, No. PN-II-PT-PCCA.2O 1 3-4-1 1 O5/2014.
Conflict-of-interest statement: No potential conflicts of interest relevant to this article were reported.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Ofelia Mosteanu, MD, PhD, Regional Institute of Gastroenterology and Hepatology Cluj-Napoca, University of Medicine and Pharmacy “Iuliu Hatieganu”, Croitorilor Street 19-21, 400162 Cluj-Napoca, Romania. ofeliamosteanu@gmail.com
Telephone: +40-742-073020 Fax: +40-264-431758
Received: September 23, 2016
Peer-review started: September 24, 2016
First decision: October 20, 2016
Revised: November 17, 2016
Accepted: December 8, 2016
Article in press: December 8, 2016
Published online: January 7, 2017
Abstract

New technologies in endoscopic ultrasound (EUS) evaluation have been developed because of the need to improve the EUS and EUS-fine needle aspiration (EUS-FNA) diagnostic rate. This paper reviews the principle, indications, main literature results, limitations and future expectations for each of the methods presented. Contrast-enhanced harmonic EUS uses a low mechanical index and highlights slow-flow vascularization. This technique is useful for differentiating solid and cystic pancreatic lesions and assessing biliary neoplasms, submucosal neoplasms and lymph nodes. It is also useful for the discrimination of pancreatic masses based on their qualitative patterns; however, the quantitative assessment needs to be improved. The detection of small solid lesions is better, and the EUS-FNA guidance needs further research. The differentiation of cystic lesions of the pancreas and the identification of the associated malignancy features represent the main indications. Elastography is used to assess tissue hardness based on the measurement of elasticity. Despite its low negative predictive value, elastography might rule out the diagnosis of malignancy for pancreatic masses. Needle confocal laser endomicroscopy offers useful information about cystic lesions of the pancreas and is still under evaluation for use with solid pancreatic lesions of lymph nodes.

Keywords: Endosonography, Endosonography-fine needle aspiration, Contrast-enhanced, Harmonics, Elastography, Endomicroscopy, Pancreas, Lymph nodes, Cyst

Core tip: Contrast-enhanced harmonic endoscopic ultrasound, elastography and needle confocal laser endomicroscopy represent new, emerging technologies for improving the diagnosis obtained using endoscopic ultrasonography. This paper reviews the principle, indications, main literature results, limitations and future expectations for each of these methods, such as their use in the guidance or orientation of endoscopic ultrasound fine needle aspiration, molecular imaging and neurophysiology assessment in gastroenterology.