1988 Volume 30 Issue 6 Pages 1205-1212_1
The evaluation of color plays an important role in the endoscopic diagnosis. Analysis of color of the gastric mucosa was performed by the Lab color system of the images from the electron endoscope through the image processor. Firstly, we investigated the relationship between the distance (x) of lens-object and numbers of pixels (y) of sampling images from a disk sized 5mm in diameter. The regression equation was log y=4.39-0.041x. Secondly, a white disk similar to the JIS9.0N having almost the same polar coordinates (32.18±0.41mm, 22.66±0.19degree ; mean±SD) seated in the gastric mucosa which was positioned in the center of the endoscopic monitor was used as a standard color in this system. There were no significant changes in the chromatic difference but the psychometric lightness (L) and the chromaticity coodinates were altered by changing the distance of lens-object. These findings suggested a possibility of the numerical evaluation of the color difference between a white disk and the endoscopic appearance of gastric lesions using this analysis and decision figure of color deviation. Analysis of eight patients with gastric cancer demonstrated that the hue and chroma differences of well differenciated adenocarcinoma were more reddish and vivid than those of poorly differenciated adenocarcinoma.
