title: Comparison of image quality between electronic and mechanical radial scanning echoendoscopes in pancreatic diseases.
abstract: OBJECTIVE
  It is common knowledge that endoscopic ultrasonography (EUS) can accurately diagnose pancreatic diseases. Echoendoscopes for EUS are roughly classified into two categories, the mechanical radial scanning echoendoscope (MR-ES) and the electronic linear array echoendoscope, both of which have their merits and demerits. In 2000, a newly designed echoendoscope, the electronic radial scanning echoendoscope (ER-ES), appeared. The aim of the present study was to compare B-mode image quality between the ER-ES and the MR-ES in pancreatic diseases.
  
  
  METHODS
  Patients with pancreatic diseases (30 cystic diseases and 22 solid diseases) underwent EUS with both ER-ES and MR-ES. The B-mode images obtained using both echoendoscopes were graded using a scoring system and statistically analyzed. The assessed point for cystic lesions was the existence of mechanical-noise-like ring-like artifacts derived using multiple reflections ('ring-down'), grating robe and so on, and that for solid lesions was the scale of penetration. The authors compared maneuverability, endurance and endoscopic images between the two types of echoendoscopes.
  
  
  RESULTS
  The ER-ES had a significantly higher score than the MR-ES (P < 0.05) in the analysis of both cystic and solid diseases. There was no apparent difference as to maneuverability, endurance and endoscopic images.
  
  
  CONCLUSIONS
  Ultrasound images acquired by ER-ES appear better compared with those acquired by MR-ES.
authors.affiliation: Second Department of Internal Medicine, Nagoya University School of Medicine, Nagoya, Japan.
authors.forename: Katsushi
authors.initials: K
authors.lastname: Niwa
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Hirooka
authors.forename: Yasumasa
authors.initials: Y
authors.lastname: Niwa
authors.forename: Akihiro
authors.initials: A
authors.lastname: Itoh
authors.forename: Naoki
authors.initials: N
authors.lastname: Ohmiya
authors.forename: Senju
authors.initials: S
authors.lastname: Hashimoto
authors.forename: Hideki
authors.initials: H
authors.lastname: Ishikawa
authors.forename: Naoto
authors.initials: N
authors.lastname: Okada
authors.forename: Terutomo
authors.initials: T
authors.lastname: Itoh
authors.forename: Hidemi
authors.initials: H
authors.lastname: Goto
mesh_terms: D002908:Chronic Disease; D004581:Electronics / Q000295:instrumentation; D019723:Endoscopes / Q000592:standards*; D019160:Endosonography / Q000295:instrumentation*; D006801:Humans; D019563:Mechanics; D015588:Observer Variation; D010181:Pancreatic Cyst / Q000000981:diagnostic imaging; D010182:Pancreatic Diseases / Q000000981:diagnostic imaging*; D010190:Pancreatic Neoplasms / Q000000981:diagnostic imaging; D010195:Pancreatitis / Q000000981:diagnostic imaging