Specifications of endoscopic ultrasonography.

In this paper we are going to describe the specifications of endoscopic ultrasonography using the equipment type III (Olympus GF- UMI ) on a basis of experiences in 45 patients during the past one year. The main body of the instrument is a standard type of gastroscope, Olympus GF-B3. The ultrasonic probe is incorporated into the tip of the endoscope. This instrument makes possible endoscopic visualization of the UGI tract and, at the same one time, allows us to do ultrasonic scanning of internal organs in the neighbourhood of the UGI tract. The better resolution of ultrasonic image is definitely obtained with this instrument than that of the conventional ultrasonography because its ultrasonography is intraluminally performed with high frequency transducer of 7.5 MHz and the image is never disturbed by the gastroduodenal gas nor the abdominal wall tissues. Endoscopic ultrasonography using the equipment type III is useful as a new diagnostic tool of great value in gastroenterology. However, there still remain a few mechanical points to be improved. It is desired that the rigid section of the tip of the endoscope is shortened more and the stability of the endoscopic image is guaranteed. These improvements would heighten its diagnostic value.