The diagnostic and therapeutic roles of colonoscopy

Examination of the anus and rectum using various instruments has been available since the time of the Egyptians and Romans. Until the development of incandescent light, visualization was difficult, using only mirrors or candlelight. The advent of electricity allowed for development of a lighted rectosigmoidoscope by James P. Tuttle in 1903 [60]. Visualization proximal to the rectosigmoid junction, however, was difficult due to the rigidity of the instrument and the anatomy of the rectosigmoid junction and the sigmoid colon. In 1928, Hoff [35], a radiologist, used a rubber tube to intubate the cecum in a retrograde fashion [9] using fluoroscopic guidance. However, Bergein F. Overholt is credited with the development of a flexible, fiberoptic sigmoidoscope in 1963 [71].