[The function of the endoscope].

The origins of the endoscope can be traced back to the anoscope, which was known before the time of Christ. Later, after Bozzini observed the rectum and larynx in Germany in 1807, the endoscope progressed from the rigid to the flexible gastroscope, from the gastrocamera to the fiberscope, and finally to the videoendoscope. At present, the endoscope is used for patients of all ages, and can be inserted not only into digestive, urinary, and respiratory organs but also into the cardiovascular system. An endoscope consists of the following; a lighting system (to illuminate inner cavities); an image transmission system (to send an image outside of the body by means of an objective lens which focuses it on aligned image guide fibers or a CCD); channels for air (to inflate the body cavity and for suction to remove fluids) and water (to wash the objective lens and to introduce biopsy forceps), and a bending mechanism to deflect the endoscope tip. The colonoscope requires further refinement to perform such functions as painless insertion into the deep colon, observation free from blind spots, and the new therapeutic treatment for microcancer.