[Endoscopic ultrasound scanning of the upper gastrointestinal tract. Preliminary results]

International interest in endoscopic ultrasonic scanning (EUL) for assessment of mural and extramural pathology in and around the upper gastrointestinal tract has increased during recent years. Since 1. February 1989, the surgical gastroenterological department D in cooperation with the ultrasonic laboratory in Gentofte Hospital has undertaken EUL on selected patients employing a recently developed Picker-Pentax ultrasonic gastroscope. The apparatus consists of a forward viewing fibreoptic gastroscope with a 5 MHz curved electronic ultrasonic transducer mounted immediately behind, the optic. The plans of scanning is longitudinal in the length of the gastroscope. On the basis of in vitro ultrasonic examinations and EUL in a total of 80 patients during a period of 12 months, the preliminary experience with the above mentioned apparatus is described. It is concluded that the 5 MHz transducer is not sufficiently high frequent for detailed examination of the mucosa and the walls of the gastrointestinal canal whereas deep penetration and imaging of the surrounding organs and structures is satisfactory. The method demands great endoscopic routine and extensive UL experience as the UL sectional image is unpredictable and difficult to define, one of the reasons being that the transducer is not visible through the gastroscope. The indications for employing the apparatus described here are not completely elucidated and assessment of the diagnostic certainty of the method requires more numerous and controlled investigations. The authors consider that EUL with linear array transducer as the most recent invention will result in increased diagnostic information in gastroenterology.