Development of the ultrasonic probe produced application to the gastrointestinal diseases easily. But in the cases with colonic lesions in the proximal part, the length of the probe sometimes became insufficient. According to the wide application of the probe to the colon disease, elongated probe was developed to avoid the difficulty of manipulation.
Twenty seven cases of colorectal flat lesion were examined using long ultrasonic probe (XUM-3T, Olympus Co Ltd) and 31 cases were examined using ordinary probe (UM-3R) from October 1995 to May 1996. XUM-3T (20MHz) was elongated about 200mm from ordinary probe (UM-3R) . Controlability and quality of picture were studied using these probes.
Controlability in the proximal part of colon, long type probe was used in all cases (100%) but cases with UM-3R was disturbed in a few cases (70%) . Visualization rate was 92.6% with XUM-3T and 87.1% with UM-3R in the whole colon. Especially in the proximal part of colon, it was 71.4% with XUM-3T and 80% with UM-3R, respectively.
In summary, a long ultrasonic probe was useful when the lesion was located in the proximal part of the colon without evidence of diminishing quality of ultrasonogram.
