A New Instrument for Measurement of Gastrointestinal Mucosal Color

We designed and produced a new instrument that measures the color of the gastrointestinal mucosa during conventional endoscopic examination. The instrument consists fundamentally of an optical fiber sensor and a light source. One end of the optical fiber sensor is connected to the light source and a commercially available spectrophotometric colorimeter, while the other end is passed through the biopsy channel of a commercially available endoscope and placed in contact with the gastrointestinal mucosa. The color of the mucosa is then measured. To evaluate the accuracy of color measurement, the instrument was used to measure the color of 108 color chips belonging to the color range of the gastrointestinal mucosa or surrounding regions, selected from the Munsell Book of Color. The instrument correctly determined the relative hue, chroma and value of all 108 color chips tested. It also had the advantages of consistently measuring the color chips under standardized conditions and of promptly displaying the color readings during endoscopic examination. This instrument was also used to measure the color of the mucosa at different sites of the upper gastrointestinal tract in 20 patients. There were no noteworthy problems in using the instrument clinically. Mucosal color (hue, value and chroma) of the upper gastrointestinal tract was demonstrated to have specific characteristics according to the region measured. The instrument provided highly accurate, objective information that facilitated the distinction of slight differences in mucosal color, an important factor in the endoscopic diagnosis of gastrointestinal diseases.