Abstract
One of our recent interests in gastrointestinal endoscopy is how to diagnose minute lesions correctly. For this purpose, several new approaches such as dye-spraying method and close-up observation with the use of a magnifying endoscope have been attempted. We have previously reported that the endoscopical magnifying observation by using a mag-nifying colonoscope, type CF-MB-M, which is able to magnify the colonic mucosa about 10-25 times larger, is useful for the observation of minute mucosal changes and the early detection of colonic cancer. A newly developed magnifying colonoscope, type CF-HM, was deviced by Olympus Optical Co. Its close-up observation enables us to magnify the mucosa about thirty-five times larger than the usual colonoscope, so that minute pits, sized 40-50p in diameter, may be clearly in-spected. Working length of CF-HM is 1420mm, which is long enough to observe the ileocecal area. The tip-bending mechanism of the scope is strong enough in four directions. During the last five months, 120 examinations were performed in 85 cases by using this CF-HM. After the usual preparation for colonoscopy, the mucosa was observed in the same manner as in conventional colonoscopy. Then, in order to make the magnifying observation easier, 0.2-1.0 % methylene blue solution was sprayed directly on the mucosal surface through a tef lon tube passed through the biopsy channel of the scope. Helped by a zooming effect of the lens system, both an ordinary distant view and amagnif ied close-up view can be commanded with ease. Minute pits of the mucosal surface were visualized more clearly than in the observation by the conventional magnifying colonoscope, type CF-MB-M. This is more favorable to dis-tinguish the stage or severity of ulcerative colitis or to differentiate an early cancer from a benign adenoma. The usefulness of CF-HM was emphasized from the viewpoints as a pan-colonoscope to examine the whole parts of the colonic mucosa and the possible role of an excellent magnify-ing colonoscope at the same time.
