Comparison of image quality between electronic and mechanical radial scanning echoendoscopes in pancreatic diseases

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.

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.

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.

Ultrasound images acquired by ER-ES appear better compared with those acquired by MR-ES.