Evaluation of a new 30-MHz Three-Dimensional ultrasonic probe and software for real-time image reconstructions of gastrointestinal lesions

Background and Purpose: High-frequency ultrasonic probes in endoscopic ultrasonography (EUS) are increasingly employed to evaluate gastrointestinal lesions. In the three-dimensional (3D) reconstruction of data obtained by helical scanning, both radial and linear ultrasound images are displayed on a monitor in real time, however, reconstruction of the surface-rendering image (SRI) inside a digestive tract requires an offline viewing system (MAJ-2000; Olympus). The purpose of this study was to evaluate the use of a new 30-MHz 3D probe (XUM-DP30–25R; Olympus) and 3D software (MAJ-1330; Olympus) for real-time data reconstruction.

Subjects and Methods: 3D-EUS was performed in 77 patients with GI lesions (esophageal, 12; gastric, 27; colorectal, 38) from October 2004 until December 2005, using a water-filling method under direct vision. The ultrasonic cross-section images were compared with histological sections cut in the scanning direction. The ultrasonic SRI was compared with the endoscopic findings.

Results: The ultrasonic gastrointestinal wall structure showed up to 11 layers using the 30-MHz probe. Using the software, the 3D-ultrasonic SRI of the lesion was similar to that observed by endoscopy. However, in terms of the visibility of SRI and the ability to reveal the shape of lesions, the software was no match for the offline viewer system. Arbitrary cross-sectional images of the lesions could be demonstrated in any chosen plane. This mode allows the endoscopist to observe the junction of the head and stalk of a pedunculated polyp. Nevertheless, several existing problems with 3D-EUS, including ultrasonic attenuation and pulsation, must be solved to take full advantage of this technology.

Conclusion: Further investigation of the new 30-MHz probe and 3D-EUS software will facilitate better diagnosis of gastrointestinal lesions.