An endoscope is an instrument that allows a doctor to look inside your body. There are endoscopes to examine the lungs and the windpipe, the lower bowel, the bladder and joints such as the knee, as well as the oesophagus, the stomach and thee duodenum.
This article is concerned with endoscopes used to look inside the oesophagus, the stomach and the duodenum. The early endoscopes used lenses and mirrors, but 30 years ago these were replaced by fibreoptic instruments that gave the operator a clear, direct view of the inside of the stomach.
Modern endoscopes are very advanced bits of technology (and thus extraordinarily expensive), consisting of a flexible piece of tubing, the tip of which can be controlled by the operator. Older all endoscopes have optical fibres along their length, but modern instruments actually have a small video camera in the tip and images are carried electronically direct to a video screen. The instrument also has other channels for suctioning stomach juice, blowing air to inflate the stomach and passing specialised forceps to take tiny biopsy specimens.
An endoscopy test (often called gastroscopy or simply the telescope test) is now the most accurate and most useful way of investigating the different causes of indigestion. It is the best way of diagnosing peptic ulcers and stomach cancers, and it can also be useful in diagnosing Helicobacter pylori infection. As well as giving the operator a clear view of any abnormalities, it also allows him or her to take tissue samples (biopsies) if necessary and can be used for treating other complications such as narrowing of the oesophagus.