'Endoscopy' means 'looking inside' and typically refers to looking inside the body for medical reasons using an endoscope, an instrument used to examine the interior of a hollow organ or cavity of the body. Unlike most other medical imaging devices, endoscopes are inserted directly into the organ.
The first endoscope was developed in 1806 by Philipp Bozzini in Mainz with his introduction of a "Lichtleiter" (light conductor) "for the examinations of the canals and cavities of the human body". However, the Vienna Medical Society disapproved of such curiosity. The use of electric light was a major step in the improvement of endoscopy.
Basil Hirschowitz and Larry Curtiss invented the first fiber optic endoscope in 1957. Earlier in the 1950s Harold Hopkins had designed a "fibroscope" consisting of a bundle of flexible glass fibres able to coherently transmit an image. This proved useful both medically and industrially, and subsequent research led to further improvements in image quality. Further innovations included using additional fibres to channel light to the objective end from a powerful external source, thereby achieving the high level of full spectrum illumination that was needed for detailed viewing, and colour photography. The previous practice of a small filament lamp on the tip of the endoscope had left the choice of either viewing in a dim red light or increasing the light output - which carried the risk of burning the inside of the patient. Alongside the advances to the optics, the ability to 'steer' the tip was developed, as well as innovations in remotely operated surgical instruments contained within the body of the endoscope itself. This was the beginning of "key-hole surgery" as we know it today.
The gastrointestinal tract (GI tract): Beginning from the oral cavity extending up to the rectum, the gastrointestinal tract is one of the longest organ, working in extreme precision with liver, gall bladder, pancreas to achieve absorption of nutrients.
Examination of the digestive system involves imaging, either radiologic or endoscopic. Endoscopy however has the advantage of real time intervention to aid diagnosis in the form of ability to biopsy suspicious lesions, or offer therapeutics in the form of securing bleed, placement of stents or resecting mucosal / submucosal tumors.
Endoscopic examination of the gastrointestinal tract involves, direct visualization of mucosa, with a gastroscope, one can reach up to the duodenum and with a colonoscope up to the terminal part of the small intestine i.e. the ileum.
Endoscopy of the gastrointestinal tract involves the following:
Although endoscopic examination can be done quickly under topical anesthesia, in the west it is always done under conscious sedation (Midazolam/Propofol). However in India, due to cost concerns among others issues, usually diagnostic procedures are done under topical anesthesia.